Monday, December 26, 2005
Sunday, December 18, 2005
Used the Unistar mount which is easy to setup and use, 20mm Widescan view is less great that the 13mm Nagler view, which is simply optimal I would say, at least for visual impact and contrast. Also taken some afocal shots, but it's going to be no good since my 12x DC is not good at that.
Wednesday, December 14, 2005
We know that webcam has a very small chip with limited amount of pixels, and if we want more field, we will usually make mosaic.
Making mosaic is quite tedius and hard, for examples, to fully utilize only 40mm of aperture, I will need over 40 raw frames stitched together to ensure enough overlapping. It's hard to imagine if one use a larger aperture, it would mean a lot of work.
Attached please find an image taken with a webcam, it has more than 640x480 and it's wider than a webcam can give, but I don't need to go through the stitching work. It's just a proof of concept shot, so don't let the poor quality to turn you down. :)
The key is to use "expand image" is registax.
In around the middle of the image, you can see a sunspot. To capture a wider area around the sunspot, I start the AVI capturing on the left of the sunspot, keep it there for a period of time, say 20s and then you start to slew your mount slowly to the right, so the sunspot is now on the left without stopping the capture, now stay sometime on the right of the same sunspot.
So, the above AVI contains both the images of the left, middle and the right of the sunspot. Notice that it's just a single AVI.
To stack it, make sure expand image is selected, and you align using the middle sunspot. The resulting stacked final will contain both the left and the right of the sunspot.
Such trick should be useable on the moon as well, the good thing is:
1. one saved time to stitch
2. one saved time to adjust brightness contrast and those stuff before stitching
3. one saved time without having to derotate the frames
4. one can 100% sure about overlapping
I shall try more to see if it really works, and also, I believe instead of from left to right, one can even go up and down, given a common patch is available for alignment during the stacking process.
Saturday, December 10, 2005
The Autostar cannot locate it well, seems like it's not very accurate to put Sun as an asteroid, anyway.
The Sun is very quiet, with a small sunspot, but when tuning the t-max, I can see several nice filaments on the surface, I can also see a plague somewhere, and it should be the remain of 826 (?) forgot the number.
Still got to find a method to balance the SM40 on the ETX.
Thursday, December 08, 2005
But here it is.
1. Capturing: use all the same settings, make sure exposure are the same. capturing from bottom to top, to avoid backlash, start in the east and match to the west; after completing a series of the same DEC, adjust DEC to capture the next series.
Allow more overlapping. I was too greedy and aggressive at first and thus the first strip cannot be merged to the rest...
2. Processing: turn off predict track, since the subtle detail on the solar disc is better non-tracked than tracked. disable stretch histogram, expand image can be left on or off. Finally, wavelet process the stacked result briefly, but remember to use the same amount of wavelet profiles. This step will allow stitching software to work more effectively.
3. Stitching: stitch all at once, don't do it piece by piece.
Wednesday, December 07, 2005
Monday, November 28, 2005
Shall use expand image to ease the effort of taking raw AVIs to do mosaic, I expect originally around 30 AVIs can be made to around 20 AVIs with good overlapping.
Time to make a new camera again. :-)
Sunday, November 27, 2005
Today no beautiful active region but some beautiful prominence.
Did captured 30+ AVIs to mosaic together, see how's it come out.
Sunday, November 20, 2005
Saturday, November 19, 2005
Sunday, November 06, 2005
Saturday, November 05, 2005
Friday, November 04, 2005
Captured 3 clips using color toucam, the middle one has some parts covered by cloud, 5x Powermate alone. Tried to stack 2x on 5x, but the seeing does not support, a blur patch of light, featureless, so didn't capture any of them.
Sky90 was capable enough to deliver that image scale, since nearly no chromatic abberation can be seen.
Finally, used 13mm Nagler + 5x to observe, can see the poor seeing easily. Also, tried to use binoviewer, can reach focus, but can see some strange reflection. I remember that I saw it before... still dunno why. Put the 2x in, and it's even worse. Both can reach focus with the 2x SCT corrector before the diagonal.
Sunday, October 30, 2005
Monday, October 24, 2005
22/Oct: Did some b/w webcam solar imaging inside home when Alby was sleeping, found a tiny crack on the CCD protective window, I got to track it poorly in order to erase that crack after stacking. Need to find a long term solution for b/w solar imaging. The result was not bad, afterall. I even got an 1 hour sleep afterward. :-)
23/Oct: Did some afocal imaging inside home when Alby was sleeping, should not give any decent result, time to give up that camera since it gives too much compression.
I also processed some AVI from that camera, even with -EV, it still overexposed crazily and the images are compressed way too much, can use G channel for surface detail and R channel for prominence. File close.
Friday, October 21, 2005
LXD55 was used in a non-polar aligned manner, just hand track with the control box, Ranger is used without a counter weight to maximize the clearance to be used at home, and to point outside as much as possible.
At 5x, very low gain is used with the color ToUCam Pro, transparency was nice, but cloud was floating around, making imaging a nightmare especially without tracking. I can only get a single clip with around 500 frames.
Preliminary processing reveals the detail on the Mars, despite the small image scale, I believe I caught the dust storm too, and it's already very BIG. Got to find chance to shoot in the street, or else I will get a dust filled featureless globe soon.
Wednesday, October 12, 2005
Friday, October 07, 2005
that so called ghost of 798 was several filaments... some nice prominence at the edge.
I did took one white light and a h-alpha image as well, cloudy at first but cleared around before sunset...
was a sick leave... slept and then did it, a bonus.
Tuesday, October 04, 2005
Mars was very high in the sky, barely ok with my Ranger, not EQ mounted but with the tripod pushed against the window and using the 410 head. The 410 head still works very well.
I used my Ranger since C8 was not useable at that viewing angle. With my 20mm widescan, the field was filled with stars, missed that feeling for long. Panning around with that slow motion control was nice, very enjoyable experience.
With the 20mm, and even the 13mm Nagler, the image was dead small and super bright, enough to wash out any detail... chromatic abberation is very very obvious.
Adding the 5x barlows revealed the detail inside, chromatic abberation is not much worsen, and I could see it's the "X" side of the Mars, polar ice cap was briefly detected, also those hazy atmosphere around the limb.
Everything was done within around 20 minutes, since no imaging can be done, packed up very quickly, missed this feeling for long.
Sunday, October 02, 2005
had a brief look, very quite, can see a small active region, barely resolvable.
a medium sized prominence at the edge, extends inside the solar disc to form the most notable filament at the time.
1 Oct 2005, afternoon around 4:30p HKT
Tuesday, September 20, 2005
So, this time I used a LXD55 non-aligned... AR798 has gone out of the view mostly, but on image capturing, I believe part of it was still in view, and I got an image of it as well.
Another not too small AR810 was in view and I captured it.
This time, the b/w cam is unavaiable, and I checked that focusing and exposure was a bit hard to set, but the outcome was not too bad, just some reduction of resolution, but still very useable, I mean for the color webcam.
Sun requires huge dynamic range, so I think we need more like a 16 bit camera more than anything. ST402ME cannot do faster than 1/25s render it useless for h-alpha imaging, or maybe need to use some neutral density filter to reduce light... but...
Thursday, September 15, 2005
Saturday, August 06, 2005
Tuesday, July 05, 2005
Prepare to go down to the street to shoot Jupiter while it's still not too low. Packed all the stuff, found that the trolley is missing, after extensive search, found and go.
The trolley is a bit overloaded, anyway, a short walk only.
Walked to the park which I scheduled to go, it's hidden by building or whatever.
Came back to the street near my home, the pavement seems okay, but it's too narrow, afraid that I will be kicked out by police or whatever.
Gave up eventually... very hot, tired and all wet by sweat...
Sunday, July 03, 2005
First time tried to shoot at f/36 but found it a bit noisy to use 1/500s. Let me try lower gain next shoot!
f/24 shots are all amazing to my eyes, b/w is better to detect over exposure, which is so easy for h-alpha imaging!
Saturday, June 25, 2005
However, the sun is dead silent today, nearly nothing on the surface, no sunspot, no active region. Binoviewer still reveal many subtle detail but those were hard to capture and align during stacking.
Few prominence but does not worth to capture.
Tuesday, June 14, 2005
This is also the first time that I was able to capture some decent high resolution solar disc detail. I used a 2x barlows and I believe that 3x could be used too. The exposure time is 1/1000s with 20-30% gain. So, there're still room for pushing further. It's just f/24 and I believe f/36 could be nice by over-sampling a bit, it should not be a problem on the ToUCam.
A b/w webcam should be even better, but anyway, the investment is not very much like I wanted at the moment. So, I will stick at 2x2 mosaic at high resolution. Whole solar disc will be using a DSLR which will be purchased probably next month, after the D50 is released (hopefully the price of 350D will be pushed downward further).
If I were to play mosaic for full solar disc, I will probably need to write a software to track and to aid positioning the telescope, solar disc hardly has enough landmark to let me frame accurately to make a mosaic that large. Maybe spend time to study ASCOM.
Prominence turn out to be easily captured, also got a photograph on that day.
Both solar disc image and prominence has a very narrow correct exposure range, due to the narrow dynamic range of the webcam, especially for the sun.
I'm happy with the result. Should try to further process that short video clip, and probably to play false color with yellow/orange instead of currently orange/black.
Thursday, June 09, 2005
cannot really capture it since when Jupiter is in better position, it's already finished... too tired to buy the setup out to shoot, so bad.
Monday, May 30, 2005
Monday, May 16, 2005
Saturday, May 07, 2005
The Sky90 did quite well on the TG-SP II for planets, acceptable and it's the most portable rig for planet imaging... Got to find ways to use C8 however.
Results are okay, better than forcing myself to use C8.
Got to find chance to shoot with Ranger reduced to 52mm aperture, should be quite fun.
Saturday, April 30, 2005
Sunday, April 24, 2005
today, woke up and wait for shooting... transparency was high but within 10 minutes, all gone wrong, cloudy..~!!! could even see the moon... maybe God asked me to sleep earlier today... oh... I just want one/two clips... while waiting for the jup to clear my window... die....
Friday, April 22, 2005
Later tried on Jupiter, no chance to collimate on any star, and I used one of the Jovian satellite to check collimation, seems not bad. Anyway. At f/20, the detail level is even less than f/10 due to overwhleming noise.
But someone else managed to get f/30 shots... how come?! shall really investigate.
Wednesday, April 20, 2005
Back to my queston, I used a webcam, a Ranger, SM40 with BF10.
I found that prominence and surface detail requires very different exposure setting.
I found that, surface detail reveals itself at the lowest exposure among all the h-alpha details, the correct range is very narrow and the image on the display will be red (normal) and it's quite hard to see it bright day light even I cover myself... maybe my eyes are too weak on red...
on pushing up the exposure, surface detail will be washed out and prominence will come into the view. Again, the correct exposure range is quite narrow, or else you saturate the brightest part very easily.
the funny thing is, if I further push up the exposure, the surface detail will re-appear, but this time, it's in orange but not red.
H-alpha should be red, I was puzzled and I spent time to think of it... why is that?
My preliminary thought is that, due to the high exposure setting, h-alpha signal got sneak into the G and B channel of the webcam. At this setting, normal R channel will be saturated, and so with G and B signal, the surface detail re-appeared. Prominence is about right in R channel as well.
Any idea, comment? Thanks...
Thursday, April 07, 2005
Also had a look on Saturn by using the Unistar Light plus Ranger, since even with the TGSP II, I won't be able to point to it. So, it's a goodbye to Saturn for imaging at home.
Seems like it's a BIG hindrance for me to continue my home imaging except the sun and the moon.
Possible solution is to find a shorter tripod, or to find an alternative way to motorize my Giro mount again, but I dare not to do it all over again. Or maybe buy a smaller OTA? Or just get a small fork mounted computerized scope so that I can push it out from the window?
Tuesday, March 29, 2005
I was addicted.
prominence extends far out from the solar disc, and then curved backward to form a filament on the solar disc... hard to take image... let me learn...
my new DC is not suitable for any kind of astrophotography, huge vignetting... at any zoom.
Sunday, March 27, 2005
the t-max tuner is really important, once set, several huge prominence come into the view... superb... I just want a larger slit and have some shots if possible... X(
they're fountain like... amazingg!!!
Friday, March 25, 2005
Sunday, March 06, 2005
That place was not very dark, but dark enough to be enjoyable.
Not very cool, but quite a lot of people there, noisy.
Short summary of targets that I hunted and observed: M36, M37, M38, M35, M1, M45, M42, M44, M67, M41, M79, M93 , M46, M47, M50, M48... :)
Seeing no good, since I couldn't even see cassini division despite saturn is quite high... stars are fuzzy patches of light...
Friday, March 04, 2005
Tuesday, February 01, 2005
They're not in good order, but date will be found in the title if possible. On migrating the log entries, I found that it's really nice to bring back old memories. Even better than photographs alone.
So, from this point onward, the reports will be in proper order.
After the purchase of the 6.3mm Celestron Plossl, I've just observed with the C90 for once only and on that night, my two favorite planets were gone from the night sky. Therefore, I've only used 159X that the 6.3mm offered on the moon, while it's breath taking already for a relatively
new amateur like me.
Tonight, it's virtually the first observing session after the purchase of my Ranger. I always have an idea in my mind, and it is to use the 6.3mm with the barlow in my C90. I guess people always want to try higher power. With the 6.3mm with the Orion Shorty Barlow in the C90, I can get 317X which is far beyond the ability of the quality and the aperture of this small scope. The manual states that we can push it up to 210X, while I have no way to verify it. I've only a 12mm and it yield only 167X and the next step is 317X.I tried the C90 on the Jupiter first. At 40X with the 25mm Celestron SMA, Jupiter is a little disc and all the Galileo Satellites are in the view. With more experience, I noticed that there're servere chromatic abberation. I guess the major source of this error, is from the eyepiece.
I tried to use 83X with the 12mm Celestron SMA, I could see two cloud bands, but they were not as contrasty as in the Ranger (76X with 6.3mm Celestron Plossl). Central obstruction? Less perfect opticals? I guess both.
Next, I tried out the 12mm Celestron SMA with the barlow. It yields 167X, and the view was alright, but again, not as contrasty as that with the Ranger at similar magnifications. Later, I tried to use the 6.3mm with the barlow, i.e. 317X. Oh! I got a fuzzy disc of light. I just couldn't improve the view by turning the focusing barrel. I would say there're two reasons: first of all, the limit for this little scope is exceeded; second, the focusing mechanism is bad. Okay, at least now I know what's meant by "the image is broken", and how blurry the view can be, if the optics is pushed too much.My next target was the Saturn. At 40X, the view is so nice. The ring was clearly visible, and I could see the gap between the ring and the little disc. Then I tried it at 83X, great! The disc is larger and things seem to be clearly. By pushing it higher to 167X, no more detail could be detected, while again at 317X, I couldn't even obtain a clear image.
Now, I know that it takes better seeing to see if I could get 317X for the C90, however, I guess it's unlikely. Maybe I should proceed to use higher magnification on the Ranger, since Tele Vue tests each Ranger up to 300X, and people reported that they could push it up to 500X in good
night. My plan is to push the Ranger to 240X by purchasing a good 10mm eyepiece, with the 5X Tele Vue Powermate. One sad thing other than the confirmed fair optics of the C90 is that, I forgot to look at the Andromeda Galaxy, which was planned originally.
7:15-7:45p, 22-Oct-98, By So King Yan Oldfield
今次突登唔帶大鏡, 但帶多 D 星圖同埋書 (DeepMap 600, 台灣旋轉星團, Night Sky Guide, Turn Left at Orion, 夜空), 目的係為左多睇星, 少玩儀器... 最後只有一支 Pentax PCF III 10x50
結果, 目的達到, 因為搵倒新野, 最深刻係 M15, 茂叔畫個視場出黎, 發覺同 Turn Left at Orion 既圖畫係一樣既...!
仲有其他野, 不過唔係好記得... M31 越夜越美麗, 土星出黎既時候, 用相筒睇, 大家都覺得睇倒個環既方向, 因為未講, 大家都講得出, 而且係一樣!
呢次有好多稀客, 原因係因為呢次係露營, 唔係淨觀星, 所以多左好多人...
我地大部份人係第一次去呢度露營, 論環境, 呢度真係一絕, 因為交通尚算方便 (即係唔使行咁多), 而且景色怡人, 風水又好...
今次係中秋, 所以主菜始終係露營, 唔係觀星... 但原來基本天文知識係好有用既, 因為呢次個天蓋就係按住黃道 (即太陽行過既軌跡) 而設計, 叫一班頹友可以訓晏 D...
一上船, 天開始黑, 已經見倒比城市多好多星, 正!!!! 到左碼頭, 已經可以見倒大三角同佢地所屬既三個星座...
講返觀星, 今次簡直係齊鏡又齊人... 我地有 Pentax PCF III 10x50, 又有 Celestron 10x60, 仲有一支新既 11x70... 單筒方面, 當然有我既 Ranger 啦... 是晚我話之各位死, 一到步既刻映月光... 十四既月光仲有少少 terminator, 都仲映倒少少立體感, 同時間, 又能夠映倒放射紋, 實在太好喇...
當然, 到左食野既時候, 我一定要停一停, 食飽個肚, 先至可以繼續啦! 如果唔係點捱到咁夜!
等食之間, 各位已急不及待走到營的另一邊 (避開營燈), 開始睇下星喇... M7 同 M8 當然要趁早喇... 不過因為已經低左少少, 所以明顯無咁精采, 不過都好! 差 D 唔記得有稀客添! 立即要指下天上面最易認既野, 呢個當然係夏季大三角咁啦! 跟住就天鵝座, 天鷹座, 天琴座, 當然有牛郎, 織女咁啦... 天蝎已經唔易認啦, 因為太低, 所以最後講埋茶壺就收工...
原來雙筒係咁難用既, 因為稀客們話肉眼望倒想睇既野, 但擺埋雙筒, 就立即迷失方向! 做壞人都要做一次, 惟有叫佢地用遠處既燈光 practise 一下先啦, 效果如何不得已知, 因為大家都忙於觀星, 找自己心入面想搵既野... 奈何月光太勁, 搵倒 M31 再教人搵, 都發覺有困難, 我估所有人都搵倒, 不過只係搵倒都唔覺得有乜特別... X(
突然想起, 要映下北極星附近既天區... 60s 曝光, 320mm (135mm equivalent), D 星都好似全部唔轉, 勁! 再試下同樣方法映仙后座附近既天區... 有人問我係咪流星黎喎! 仙后座都唔係距離北極星咁遠唧, 乜已經分別咁大!
等下等下, 乜有粒咁光既星呢! 我以為係獵戶膊頭, 原來唔係... 諗真 D? 土星呀朋友! 點肯定呢? 支 Ranger 剛拆左出黎讓支腳出黎 mount 11x70! 我決定手持! 15 倍已經睇倒有 area 啦, 仲唔係?! 一定係啦! 嘩, 想映土星好耐啦喎! 對唔住都要架啦, 11x70 要讓位喇! 32mm Plossl + 2x shorty barlow + Ranger + Casio QV2800... 好難對焦喎... 粒土星鬼咁快... 好唔開心, 因為超難映! 算喇, 搵個七姊妹星團大家睇下仲好, 起碼開心 D 丫嘛... 用個 zoom frame 到靚一靚先俾各位老細睇!
係喎, 點可以唔 show 土星俾各位稀客睇睇呢! 當然, 呢個差唔多可以話係全天最勁既天體, 絕對唔會令各位老細失望... 由 75x... 再推到 200x, 大家都睇過... 好野黎丫嘛! 不過去到 200x 其實無乜著數, 不過睇黎
人人都鐘意大, 唔鐘意細但 sharp D... 算, 有乜所謂, 最緊要開心丫嘛... 不過要上到 200 倍, 每次只可以一個人睇, 之後我又要 center 返, 再可以到一下個... 所幾辛苦, 但又好鬼開心!
大家都睇完之後, 各人有各人再睇星... 當然, 拿雙筒既方法, 大家都似乎掌握倒, 無咁震啦起馬... 但原來有人嫌雙筒睇倒太多星, 完全迷失方向喎... X(
我死唔斷氣, 再戰土星... 呢次定死 1/8 秒曝光, 對焦就用令到粒土星最光為止... 好似有 D 野喎! 放大睇下... 喂! 我映倒個環啦!!!! Yeah!!! 太興奮添... 諗起要 stacking, 立即唔使錢映多幾十張先... 一共映左 31 張, 其中有幾張用左唔同既 ISO settings... 相機睇都幾好, 不過粒土星都係細左少少...
搵個老細搵志光座丫... 衣架星團, 其實係... 志光哥好似搵唔返喎, 最後都係阿茂勁, 第一個搵倒, 之後志光哥教埋我再搵... 然後用 Ranger 睇, 好似無乜著數, 但勝在 mounted, 個個都可以睇丫嘛... 不過後來好>似都有稀客搵倒啦喎... 幾好丫!
一個出場係獵戶座, 好易認... 但個星雲就... 呢次實在太差啦... 費事介紹, 以免以為係廢物, 下次先啦...
木星始終未能趕及訓覺之前升高 D, 所以都係留返下次先...
今次發現基樑買左支 11x70 之外, 仲有一個非常正既旋轉星圖, 係我一直想買果個... 仲加左紅色小電筒, 簡真係完美配套...!
我們到了上次阿茂報告的新地點... 由巴士站直入要步行四十分鐘 (!!!)，沿路不知連續幾天好天也會有少許泥濘... 那條路明顯不會有很多人走，雖然是山路，但也能看出那是車路，因為兩邊沒有草，中間卻有不少...
沿路都有很多溪錢，不仇迷路 (LOL)，也有金塔，墓碑和棄置了很久的汔車一架 (生滿了銹，草由裡面長出來)，十足十鬼片... 因為要探路，走到合適草地觀星的地方，最高的草長到腰那麼高... :)
遠處有荃錦公路，還很美呢 (光害倒很小)! 近處有幾座小山丘，環境其實很美， 若不是先人的居所，那裡定必是露營的好地方!
玩了一輪阿茂新置的 laptop，還是留了二十分鐘左右便離開... 我映了幾張相， 遲下 send 俾各位，水準自問十足，可以做 wall paper!
話雖如此，這還不失為一個好節目! 試想想，下了班，一班好友一同到郊外走走，原來也是一件賞心樂事呢! 極想星期日快到!
昨天晚上我們一行三個傻佬去左石澳大頭洲，發覺高壓區帶來近兩三個月黎最好既天氣，日落後約一個半小時，30 秒曝光仲可以睇天空係深藍氣既... !
一入黑，我地幾乎失去方向，打電話俾阿茂遙控 technical support 都唔掂，始終無左佢隻可以睇倒天箭座既眼!
無新野搵倒，但開始見番 D 舊朋友，好似 M31, Double Clusters...
本來諗住要摺, 但後來因為天氣太好, 決心太強, 志光哥既犧牲精神, 最後決定再戰田...!
旺角天氣好正, 屯門都係, 深藍色既天, 天蝎座頭頂三粒星, 都係尋日無既, 所以雖然 Oldfield 想去大尾篤 (東), 志光哥想去石澳 (南), 茂叔想去錦田 (北), 最後, 志光哥犧牲自己既意願, 去左錦田...
尋日發現 251M 勁快, 約二十分鐘可到錦田! 好似令到我地失左任何去大帽山既原因... 露營除外!
檢討後發現在大帽山從來都無新深空天體搵倒, 除左 double clusters,睇黎呢個唔係一個好地方... X(
成九點先入到錦田, 因為大家都要 compromise... 最後十點半走, 仲走左班車, 志光哥真慘, 因為第二朝要早返工, 佢又住得最遠(HK Island!)...
呢晚想搵 Omega (NGC 5139), 不過我張美國星圖無, 又可能因為真係太低, 所以睇唔倒, 但最後返屋企之後 verify 發覺有其實機會可以!算啦, 下次一定要帶 DeepMap 600....
原來志哥光話佢尋晚已經搵倒鯨魚座, 仲話中間有個鈎, 好型... 我聽佢話, 都搵倒, 惠玲 spend 左一段時間, 都搵倒... 但後來勁眼茂叔話果個唔係鯨魚, 唔知係乜... 因為都唔係果個位...
之後叫左果個野叫 "志光座"... 茂叔用大鏡搵倒, 最後我映左張相, 返屋企後發覺呢個叫衣架星團 (Cr399 - CoatHanger), 真係勁似!
Lagoon M8, M7, M6 都無問題, 又映左幾相月球, 同埋 M7... 呢次個 M7 好左好多, 因為得各方好友指點得以對焦更準! 又搵倒三件另外既 (即除左 CoatHanger) 新野: M22, M23, M25... 都係茶壺頂, 無乜難度... 搵 M13 容易好多, 因為武仙既四邊形肉
仲搵到真正既鯨魚, 仲有天箭 (只有茂叔可以肉眼睇倒)... 另外仲發現原來志光哥既 Albireo (藍橙雙星), 同我一路講既原來唔同添... 鵝頭同鵝尾原來大家無乜共識... 哈哈!
最後走既時候, 見倒一粒幾低下既光星... 當時唔知係乜, 後來check 星圖之後發現係 "北落師門"...
大帽山, 依家呢 function 唔係觀星, 依家可能只有行山, 頹露營, 或者係擋住 D 雲... 我地發覺旺角好天, 屯門好天, 但荃灣多雲, 元朗就... 都係靠大帽山頂住!
由於阿茂既誠意 (出夏令會後直去睇星唔返屋企住), 是次行程先至可以成功! 原本諗住去大帽山, 最後天氣唔係太好, 無落車, 原車直入錦田!
大氣透明度較低, 好多野都搵唔倒, 所以映左好多月球... 都算係成功, 因為呢次既月光比上次高好多, 所以無論月面光度, 大穩定穩定度都好好多...
樹殷既 1000 度菲林唔知晒出黎會點, 不過因為月光都幾勁, 加上有煙霞, 同埋第一次映, 所以期望唔係太大, 不過希望在人間丫嘛!
搵倒 M7 見唔倒 M6, 又唔係太睇倒 Lagoon M8... 映左張 Albireo, 仲有突登映到有流跡添...
約 8:20p 上倒車, 上到去都幾夜, 估唔到仲睇倒月球, 因為想玩左天文相好耐, 所以立即唔放過機會, 用 32mm Plossl (15x) 映左幾張無焦點 (afocal), 因為月球已經很低, 所以光度唔足夠, 好難對焦...
包圍曝光映左幾張, 映唔倒地照 (Earth-shine), 但有一兩張都映倒隕石坑... 算係咁啦, 第一次映...
之後搵深空天體, 搵倒 M7, 仲映左幾張相, 發覺 15 秒之後星光已經唔係點而係線, 10 秒亦尚可, 但光度明顯唔足夠, 睇黎唔用追蹤拍攝的話, 想攝倒深空天體都幾難, 可以映像既天體都好有限...
亦都映左幾張火星, 不過唔係太識對焦, 並且曝光大多數都過度左, 因為無做實驗...
後來到巴士站等車既時候, 發覺大氣透明度比起直昇機場果度好好多, 可能果個位真係有問題... 下次唔好去囉... 要試下有桌椅果邊...
尋晚 (20-Feb-2001) 上左大帽山睇星, 成個月都無咁做喇...
以前都好少春天睇星, 因為天氣唔好, 所以今次望上個天都有少少迷失既感覺...
當然, 幸好好多野都仲認得, e.g. 金星, 木星, 土星, 獵戶座, 仙后座, 金牛座, 雙子座, 御夫座, 大犬座等, 獅子座, 仲有大半個既大熊座... 因為未春得晒... :P
好容易搵倒獵戶座大星雲 (M42), 七姊妹星團 (M45), 鬼宿星團 (M44), 仙女座星系 M31, M35, 36, 37, 38... M41, 雙重星團 (NGC 864, NGC 869), M46/47 (新發現), M81/82 隱約可見但不能肯定...
試過手拿數碼相機以無焦點方法映木星, 土星, 金星, 效果不好.... :(
Monday, January 31, 2005
I forgot the exact date when I wrote that. I brough the C5 of Paul Ng with my Unistar Light on my small Gitzo, the whole setup is very light but I regret.
I found it hard to use, without my Rigel. The sky was no good that night, a very thick layer of haze is always there.
Okay, this is not a good trip at all, but it serves as a nice proof of concept about going out after family sleep and come back before the wakeup.
Thanks Josephine to give us a free ride.
The sky is nice and clear in the afternoon, we went to Tung Chung to have our short but enjoyable dinner. But when we go outside, we saw the sky full of cloud, anyway, we still proceed.
After the bus trip plus some short relax walk, we arrived and we saw an observing friend Bug who was already there, lying on the floor with his binoculars. The sky was still fully covered. Occasional cloud gap allowed us to spot some stars, but not enough for us to identify the sky. I planned to leave around 8:00p, bad.
The sky cleared up gradually. We scanned through the region near Orion with my C8, and the sky continued to clear up, and in the process, the gone through all the major winter showpieces, like the M31, 35, 36, 37, 38, 41, 42, 45, and a couple of other things like the Christmas tree cluster, etc.
Finally, the sky was covered again around 8:45p and we packed up all the thing, went home rather early, and took our bath well before 10:30p, great indeed.
One of the spikes and rubber feet of my tripod was lost in the trip, got to buy replacement. After some hunting, I found it hard to get other than from the distributor which is located in aberdeen (far far far to me) and need to buy in office hour, not to mention that I have to special order the items. When the annual leave is counted, plus the transportation fee, I end up buying from a UK vendor with about similar cost shipped to me. Finally, it costs me $270 HKD, what a big mistake!
We went there after the fellowshop on Saturday, we belonged to the same fellowship in the church. I took my new C8 Anywhere setup to the church in the afternoon, finished two fellowships and then go there together from Cheung Sha Wan at around 7:15p. The setup is light and I distributed the mount and the eyepiece box to one friend and the tripod to the other, so I can even run a very long distance with the setup! Super good!
We were all rather tired at the beginning of the trip, but I found I owed them for not giving them a peep on the Mars which attracted a lot of people from a very wide spectrum. I owed them before that I who got them attracted by the night sky but without giving them a view through my telescope.
We arrive Tung Chung well before 7:45p, and we bought some easy (cheap!) food and eat them on the way. We waited at the Taxi station and waited for nearly 10 minutes for a taxi, and it is the longest record ever. We arrived Shui Hau at 8:10p, with less than $90 taxi fee, i.e. $30 each, not bad. Personally, I used those fee complimentary ticket (10 trip 1 free) for both MTR journey, that alone saved me
$30+ dollars. You know what, the single trip time is less than one hour, and we are talking about going from the urban center to a dark place!
On the taxi, I can see the whole scorpius hanging outside, it is way better than the urban center. Getting off from the taxi, we immediately saw the milky way extended from the horizon to far above the sky near zenith! This was definitely the best view we had of the milky way!
Setting up the scope takes less than 3 minutes. Extend the tripod, screw the Unistar Lighter mount head in, put the C8 OTA on the dovetail, remove the caps, insert the 40mm XL eyepiece, snap on the Rigel Quick Finder. That's all! I found the Rigel Quick Finder remained aligned with the OTA after nearly two months since the last
M4 was our first target, without good dark adaptation, we didn't get a great view. I switched to M8, and we got a great view! M7 was even more stunning to the non dark adapted eyes. I pulled out the self printed star charts to dig into the milky way and the wonder summer sky!
The Unistar Lighter mount is so easy to use, it is not as smooth as the Giro, but it is not as heavy either. It moves and it stops as desired, which is good enough.
I learnt a new local friend locally with ICQ on the morning. We of course never meet before and we will meet on the same night. Mobile phone reception is not good and I found a family nearby when we're observing, I should aware of that.
Somehow my mobile phone began to roam using mainland network, and I received the call, and confirmed that the family is what I talked with ICQ on the morning.
I offered them some stunning objects and the children were very excited and happy to see the views. The adults are less motivated, but still they enjoyed the view.
I hunted for more objects, including those must-see show pieces like M22/M23, M13 and M11. Hunting couldn't be easier. No single object took me more than 1 minute to hunt. It is easy, and it is enjoyable!
I occassionally switch to my 20mm widescan for double magnification, globulars are better resolved but the view is also dimmer. I found I love larger exit pupil. I found some "noise" in my eyes. Maybe binoviewer can solve the problem? haha...
The list of observed was too long and it was not logged on site. I told my friend that the quality of observation time is much higher than our previous observing location, they all agreed. We hunted, observed more objects that what even ten session of other observation location could offer.
Saying all these, we stayed there for only less than 2 hours since we will want to keep more energy to go to the church on the next morning. Anyway, we hunted for over 20 objects, fully enjoyed.
We left at around 10:00p, walked outside to the bus station, waited for around 15 minutes and then I arrived home at 11:30p. Not bad indeed!
I didn't bring a lot of eyepieces with me. Only the Chinese made 2" wide angle for my C8, plus a 32mm Plossl for my Ranger and a Tele Vue zoom to play with. Balancing is an hard issue since the floor in Shui Hau is inclined. The heavy 2" wide angle is a real problem for proper balancing. I failed to get any point which will allow change of eyepiece without re-centering the target, or tighten the friction control knob of the Giro mount.
Again, deep sky hunting with 8" aperture, plus a 2" wide angle eyepiece, on the Giro mount is a very pleasant experience. Everything was so simple. Look at the chart, locate some brighter stars around the target, aim the rough area with the Rigel Quick Finder, looked into the eyepiece, it's about there, if it's not scan around slowly and the target will be right there within 30 seconds.
Quick and simple and enjoyable! I won't want GOTO of any kind, I mean if I do not go for CCD imaging.
Now, the weakest link in hunting object is not to hunt for it in the sky, but to locate which chart contains it!
Name an object, look up the index, locate the bright star, Rigel, scan a bit, here it is!!! No miss.
Many deep sky objects can be resolved with a 8", what a nice tool to play with!
M4 can be resolved rather nicely, M22, M13 is a dream. M51 shows the parent and the child rather clearly, but no spiral arm yet. M57 shows the hollow ring shape very nicely. M11 is super funny, wild duck!!! Omega Centurie is impressive and fabulous. M6 looks exactly a butterfly, M7 is a gem. M8 shows many nebulousity like M42 in a small scope. M17 is "Nike" in sky! M54, M70, M69 all reveal their
identity under the teapot.
I am sure I saw far more than I can remember. It's just a 2 hours show, time is running to fast. But it won't overwhelm a tired body even we go there after working for a whole day.
We arrived at 6:30p and we setup the 25" scope at around 6:45p. The scope was stored in several place. The secondary cage and the primary mirror was stored indoor. The rocker box plus the primary cage was stored indoor as well, but just outside the roof for observation.
We moved the primary mirror up to the roof and it was very heavy such that two persons can barely do it. This huge chunk of glass was a monster. The secondary cage was much lighter and can be handled by one person. That's important for we got to set it up on the top of the tall tall truss tube.
After the EQ platform, the secondary cage and the mirror was transported to the roof, we moved the monster size component. It was placed on top of a big trolley but we got to move it with five persons.
Setting it up was fun, but time consuming, however it worths. The first installation was not done very nicely and the primary has to be moved out and re-install to get enough room for collimation.
In short, with the 25", all clusters become open clusters. Even the highest density globular was resolved to the core at moderate magnification. The light gathering power and resolving power of the 25" is well shown even with lots of light pollution around.
For nebula and galaxies, it does not show well due to the light pollution, not much color can be discerned, again due to the light pollution, and so we said only 30-40% of the power of the 25" is shown.
All the star clusters, globular or open, show better than photograph since you can see it 3 dimensional. Staring at an object will reveal stars which are not shown clearly in the first glance, and the static cluster looked vivid and alive due to this reason.
I set a goal for hunting five deep sky objects, but I failed. First of all, the moon was brighter and more annoying than I anticipated. I could spot the M44 without problem, and after some hard hunt, I could dig out M3 which is new to me and my friends. Otherwise, all failed.
My friend got a new digital camera and it could be the major source of fun for them. He shooted to Saturn, the ring can be made out, but not cleanly. He shooted the Jupiter, but the excessive shake killed all the detail, not even the equal sign. He shooted the moon, and it gave the best result.
Other than the moon, the mount was a problem. Since I was not that energetic that day, I got only the 410 head with my C8 which is an overload. The slow motion control became very stiff, and it was very bad to hunt for new things.
I should have stayed home to shoot the planets and the moon. LOL
This time, we visit Shui Hau, which is a small village in the Lantau Island, this is also the first time I come to this site. Together with me, we have Leung Sir (Mike Leung), Paul Ng, Billy Cheung (faihoka aka in astrofarm) and Szeto Bug. We gathered at the Tung Chung MTR station at 5:00p but we started off at 5:30p due to someone come late seriously. LOL
Prior to that, I bought my trolley to take my equipments out. I didn't go for a suitcase for some people said suitcase is not robust enough for heavy stuff, and I want to put my mount fully setup during transportation which can save a lot of setup time, I will need a very tall suitcase then, tall suitcase tend to be very large which is hard to move around and excessively bulky for public transport.
I settled for a trolley which is small and retractable, it is rated for 35kg of weight, not bad. I rushed home to pack up everything for the trip within around 20 minutes and go out, eventually late for 5 minutes. Too bad and too good that someone is vastly later than me. hahahaha...
Moving the trolley is not as easy as once I imagine, but it's manageable. I believe I can do better next time. I shall write another article for transporting my equipment to the field. So, let me skip the detail here.
The counter weight get dropped onto the pavement while walking, I then secure it again but that time, it was secured by too much that it was trapped in a recessed position of the shaft and it was no longer movable and removable... bad...
We hired a taxi to go there this time, around $90 each trip. Not bad, but it's comparable to the East Dam which is actually a darker place.
The observing place is rather small, and it is along a narrow single way road and it is a place for car to give way to opposite car. There is only one police car passes by during the whole course of observation. The place is inclined, meaning one will need to spend some effort to level their EQ mount. For me, my GR2 mount and Tech2000 drive does not need leveling to tracking, I was the fastest to setup everything.
For the most night, I keep my 40mm XL in the diagonal, for it is the widest and it provides enough power to see most things. I only borrow some J-ortho from Paul for viewing the planets. I believe I shall get some more J-orthos myself someday later. The zoom has to be used with the Ranger for maximum portability only.
With the Rigel Quick Finder and a set of Telrad finder chart, I managed to clean up two small maps within about two hours. It sets my new personal record. Hunting stuff with the Giro mount is a very pleasant experience. I sweared that GOTO will not bring as much as joy as it can. Don't get me wrong, GOTO is useful for imaging: focus on bright star -> GOTO -> shoot!
Here're the hunted list:
Map 1 (6): M35,M37,M36,M38,M45,M1
Map 2 (13): M44,M67,M48,M46,M47,M93,M41,M50,M79,M78,M42,M43,Christmas Tree (NGC 2264)
Observed list: (hunted by Bug)
Comet 2002v1, Mexico Jumping Star
Chu-kwong arrives at around 10:20p and Paul and I are packing our stuff already by then. What a pity that we missed the ED114SS. Anyway.
We called for taxi for twice and until around 11:00p, we decided to walk to the bus station instead. So, be reminded that it is not a must that taxi will come to this narrow road. And it's better to make appointment with a taxi before hand. Bug was very accurate again telling us the bus will arrive at around 11:15p... nice! We arrive Tung Chung MTR at around 11:50p, so nice!!!!
I love deep sky hunting!
We gathered at 5:30p in Sai Kung and hire a taxi to go directly to the east dam, since the east dam is a restricted area, one cannot go there by other transportation. The sky was very clear all day until around 5:00p, the sky was 90% covered. We go there without hesitation however.
Arrived, we took some shots around. East dam is a very nice place, not only for stargazing but also for sight-seeing. I ate my cup noodle anyway, it was my first time to east cup noddle, I remember to take hot water but I forgot to bring a fork... oops... index finger was used. After taking the noodle, the sky cleared!
We observed a lot of things. Many deep sky objects were nake eye objects! This is probably the first time I saw and pointed my Ranger to M31. No problem. All of us found that there were so many stars under the big dog (cannis major), we didn't realize that before.
It was the first time I found M38 resolvable with my Ranger. Previously I found it was just a faint fuzzy with granularity.
It was the first time I viewed through a Leica 10x50 binoculars. The view was superb, contrasty and super sharpness. It was a bit heavy for a 50mm and the focus travel was limited, the eyecup design was clever and user friendly!
I didn't try to hunt for much new objects, I tried to enjoy instead.
We have briefly polar aligned a spaceboy originally planned to mount a C8 (overload), but the screw does not match (thread size) so it ended up for taking wide field shots with different DC.
Cloud came in around 9:45p, we called the taxi to come back earlier (10:30p originally). When the taxi came, the sky cleared again, but we left anyway.
Popped in the 40mm eyepiece, Jupiter was very white with a slight bit of chromatic abberation due to atmosphere.
Bootup the machine and plug in the webcam, found some seeing problem already. Anyway, took some images.
This time, other than the 2x barlows I've been using, I stacked in the Zhi-tong barlows to get larger view... the seeing was bad anyway, just time to do experiment. The image formed was not bad at all. However, notice that I've the lens of the Zhi-tong barlows removed, so it's just acting as an extension tube!
At such high magnification, I noticed that the backlash value has been set too high for visual observation. I hate tunning backlash during imaging, but anyway, my ToUCam has been stucked up with dust and the dead dot, so, has to place the larger Jupiter more accurate in the use-able field. :P
Call an end to the imaging after a few cheap clips due to really poor seeing, remember Jupiter has sunk quite low?!
Before stopping, I realized that M44 was just a bit lower. Popped that 40mm in again trying to see it... the 40mm was bought for this kind of large object... oh... pink background, and only a few of the stars were revealed... alright, it's the first time I caught the whole M44 with my C8 I suppose... not sure it's because of the larger field of the 40mm, or it's because of the cloud which prune away some stars....
Cheap, but enjoyed! Who cares when you didn't even think it could observe!!!
Choosing a venue alone was not easy as before, since we rarely got chance to observe outside now. We all wanted to get better views, so we narrow down our choices on Shek O' and Tai Mei Tuk and we finally decided to go to Shek O'.
This time, we didn't spend time going to the end of the Big Head Island, instead we settle at a place where the Big Head Island serves as a shelter for the only strong light from far away.
This was the first time we saw milkyway clearly in Hong Kong, it extends rather long in the sky. What a sight!
This time, I took 40lb of equipment myself, and it sets a new record here. I was using the Ranger and the evil lies on the mount, the battery and all other stuff. The GR2-DX was real heavy, and another friend took out his notebook PC for using the roboscope option. The software stowed in my microdrive inside my digital camera, and installing software in the stony place was not a nice experience after all. After several rebooting, we got the software installed.
When the Roboscope PC link was installed, the keys on the pendant will be disabled by then which was bad enough. It was hard to press the keys on the PC lying on the floor while looking thru' the eyepiece at the same time. We failed to do even a two stars alignment in such a bad environment. Too bad that those equipments were wasting our time, and wasting our effort to bring them all out. We originally think it might save our time to hunt down our targets but it turned out to be opposite!
I proposed to turn off all the electronic stuff. The GR2-DX was good enough for me to scan around, finding object couldn't be easier as before, together with the Ranger.
Binoculars observing are always enjoyable. We looked at M7 and then M6, and then M8, and then scan up around to find M22 and those Messier objects near by. I swinged the Ranger to the Antares and it immediately reveals the M4, which I could never see in my apartment even with the 8"! But it shows so nicely with my 70mm right now!
The moon came out around 9:00p and we had a peek on it and then we packed up everything and enjoyed!
The transparency has been excellent yesterday night, I could see over twenty stars despite:-
1. I'm inside home
2. Spot lights are flooding in the sky
3. I've no dark adaptation
When I was doing the alignments (C8 + driven mount), my wife told me that she was feeling sick. I need to unmount everything and took her to the doctor.
Coming back home, I resumed my observation but,
1. Inside another room, with windows closed for air-conditioner
2. Light kept on, for my baby
3. Spot lights are still flooding
4. Nothing to talk about dark adaptation
5. Bright moon was hanging right there
I could barely detect M4, and I understand I shall try to find something else. Instead of the larger scope, I turned to my little Ranger with an non-driven mount.
Having such a small limited window, I scan around exhaustively and slowly.
Finally, I found my old friend:- M7. At 15x, I could see a lot, I mean A LOT, of stars there.
Using the zoom eyepiece, I optimized the constrast by tunning magnification. At one point, I could see that the cluster was three dimensional, dim stars were sinking in the field and brighter stars were floating on top. Woo~~~
Going to another room to fetch in my better quality plossl and ortho, I could see dimmer stars better but it reveals nothing more.
Turning back to the zoom, at 60x, the apparent field of view becomes largest (~55 degree), I could really understand why people shell out BIG money to buy wide field eyepiece. With just 5 degree more, the feeling is a whole lot DIFFERENT! With the increased constrast, even thought I could no loger see the whole cluster, I found it appeared very immensely!
Of course, I shared the view with my wife (she has been better after taking medicine), and she was excited as well.
So, by ALL MEANS observe, since you could see something despite of the bad conditions.
This is the ever best view I had had for my good old friend, M7. I've never been able to spend that many time for a single object, maybe that's why it turns out to be THAT GOOD!
Yesterday night, after searching the comet I-Z (failed), I begin to find a DSO which came near my window.
I used my 70mm refractor to find it, and after looking at the star chart, I found it. It's easy in dark sky but it's not so easy to find it in the urban area. The first time my FoV covered that area which I felt confident in, but there seems nothing there.
I remembered that I read an article from a famous amateur in sci.astro.amateur saying that some objects will not be visible in the eyepiece if you just sweep across the field.
So, I stopped for a while, spend some time to look at the area which I felt confident.
After 2 or 3 seconds, the open cluster revealed itself from invisibility! I called my wife in and showed it to her, she could see if after a while too.
Then, I setup the 200mm and tried to catch it again.
The starting point was Sirius. At 62x, the sky was dark and the Sirius looked real good. I called my wife in and she said it looked like a big diamond. She told me that there's a dark thing in the center of the star, it's an indicator of two things: good collimation, focus was bad. I asked her to focus it again, and the black spot disappeared.
I then searched for M41 again. With the experience just gained with the 70mm, M41 was found much quicker. The number of stars in the open cluster was much more than with the 70mm, and I could see it immediately. Again, I asked my wife in and shared the view with her. She said there were so many stars, with different colors.
Personally, I found the view of M41 superior in a dark sky with my 70mm than the view of it at the urban center with the 200mm. Aperture is not everything, darker sky somehow and sometimes can play a more important role.
This time, I just want to take some afocal shots of the moon. I placed a wooden board over a "bamboo blanket" on top of my soft bed. The tripod could not be extended or else it would be larger than the wooden board. So bad. The setup was top-heavy. I held it by my legs, setup the remote control with the digital camera. Took some quick shots, the results were not so bad. It was a good start.
In short, we found no new object. However, we saw more detail in old objects.
First, Cassini division was very obvious, even detectable without averted vision. This was the first time with my little Ranger. We saw a number of cloud bands as well, they were not subtle. Next to the Jupiter, the GRS was excellent. Perfectly detectable without using averted vision as well. We could detect over 8 cloud bands clearly that night as well. I could also see a satellite coming out from the back-side of the planet.
M42 was fan shaped, we had never detected this shape as obvious as this time. Other dimmer objects were no as nice due to the sub-optimal transpareny.
When we arrived, the whole sky was covered with cloud. We decided to stay a while to see whether there are some other good places for observing next time. It's also nice to breath in some fresh air.
We found another place, but it's not perfect. First, it's too near the road. The head light from the cars can ruin our dark vision totally. Second, we could near nearby towns directly. Actually, our first target of that night was the Central Plaza and the second one was the Tsing Ma Bridge.
Suddenly, we saw the Sirius. We pointed there. Nothing else except the bright white star (not much chromatic abberation with the Ranger, at least not annoying). Next we found the Jupiter. No cloud belts but the four satellites were clearly visible. We tried to find Saturn (which is invisible even with 10x50 binoculars), no luck.
In between the break of the cloud, we looked at M42. And it was one of the worst sight of this old friend. We also found the Pleaides later, and it was visible through both the binoculars as well as the Ranger.
We continued to look from the break of the cloud. Finally, most of the cloud in the zenith went away. We could see two open clusters in the Auriga clearly, and we could actually detect one more, but could not see it clearly. I guess we saw M36 and M37 but just detected M38. M42 and M45 became a fine sight after the area near zenith was cleared. M45 was always amazing. Maybe we should try some afocal shots next time. Saturn's ring and Jupiter's cloud belts were clear. Finally, we found Andromeda beta and gamma (Almach) as well as detected M31 briefly. The double cluster was barely detectable at best.
We could not locate M41 this time.
The view was not good but we were satisfied.
Taking out my Ranger, I want to test the zoom eyepiece in the sharpness department. People said the sharpness drops below 12mm or 10mm. I want to verify it myself. Scanning the sky first reveal many many stars, and it proves to me that the Ranger with 20mm more aperture actually show more, regardless of the night in the High Island Reserviour. It also confirm me that if it's not the dew, the Ranger can actually deliver amazing views under darker skies.
I point my Ranger to the orange star. Strange. I guess my Ranger has pinched optics at first, I also guess that it might be due to the relatively cold weather. The star looks triangular!!! I never noticed that before. My mind is confused and I begin to blame my Ranger again (You know, I'm considering to switch to a Tak FS60C!).
No matter how, I turned my zoom to make it at 8mm, i.e. 60X with the Ranger. Hey! I see two stars!!!! It's not pinched optics, it's excellent resolution!
A familiar view! I saw that in the High Island Reservior!!! It's the Almach, Andromeda Gamma! I can't imagine that the small viewing windows (approximately 10x20 degree at most) can actually show me something!!! Especially in a real urban sky!!! Clear dark sky separate the two stars. The blue star is pinpoint, and the orange star shows it's diffraction pattern nicely, round and clear.
In order to test my zoom, I insert my 5x Powermate to the optical chain. At 100x (24mm), the double split nicely. I dialled all the way to 8mm, refocus. Hey! The stars are separated by a huge gap of absolutely pitch black sky!!! Both stars show diffraction pattern nicely. You know, it's already 300x!!! The little 70mm aperture is showing at more than 100x per inch, I consider myself crazy!!! (Okay, I didn't try to stack my 2x barlows in) Of course, in this setting, the sharpness drops but the image still didn't break down.
I tested my Ranger with the 20mm Tele Vue Plossl as well, the Almach splits clearly during better seeing. Careful observation helps. With the zoom, it also splits at around 18 to 20mm.
I love my Ranger again. I love my zoom as well, it stands up well against the fixed power Tele Vue Plossl.
When I went back home after the prayer meeting, I saw the moon from my windows. I setup the Ranger within one minute and begin observing. The cresent moon was so good in my 15x field of view!!! I could see the whole disc, with the help of Earthshine. I couldn't help to ask my little sister to look into my eyepiece! "Woww!!", was her response. I understand that she appreciated it. I pumped it up to 75x with the Powermate, she looked and wonder how nice the view was. Excellent! I pushed it further up to 150x with the 2x Barlows with the original setup, making it very long, but the view was so good!
I called my parents in and my father found it difficult to catch the view into the eyepiece, maybe the eye-relief was too much in that kind of setup. I replaced it with a 20mm eyepiece to make a magnification of 120x with the Powermate, I knew he could find the view finally when I heard the voice "woww..." from him. My mother got next but she didn't make a woww... voice and we guess that she couldn't see it. But that's not the case, she seemed not so excited as us, she described the view to us, showing that she could really saw the image in the eyepiece. Of course, she appreciated the view, but she found nothing special about it. I guess it's because she didn't know how far out there the moon really was.
I continue to watch the moon, try different magnifications, including the weird 381x and even 762x... To my surprise, the Ranger could hold with 381x actually but of course, it brought no further detail. 762x generated a too small exit-pupil, I could see nothing except my own eyes. Not bad. I keep watching the moon at 75x, finding it's the optimal for tonight. The moon sinked without a notice.
My next target was Jupiter, but I have to wait ten minutes or so after the moon disappeared.
The view of Jupiter was so good tonight, it's the best view I had so far. With 75x, I could detected three belts clearly. Pushing it up to 120x (20mm/5) or 150x (6.3mm/2) revealed the fourth belts. That's the first time I could detect four belts. Actually, I suspect I could see five of them, but I ain't so sure about that. I suspect I could also detect the GRS together with some largest festoons on the thick belt in the "lower" portion of the planet disc. It's so nice that I kept on looking it for 20 minutes or even more, before it went out of the view. The Jupiter disappeared below the tall build in front of me, and I discovered that first when the resolution of the image dropped suddenly.
After all, I found that the Celestron Plossl was the worst among my three eyepieces. The Sirius Plossl was not bad, but a dim ghost could be seen on axis. The quality of the image in the Sirius Plossl was not bad, very much comparable to the Tele Vue Plossl. But I could see no ghost in the Tele Vue Plossl. At first, I guess that the Celestron Plossl plus the Orion Shorty barlows could give some pressure to the Tele Vue Plossl plus the Powermate because there were fewer element in the Orion Shorty, but I found it NOT to be the case. Even the Powermate plus the Sirius Plossl showed me more than the Celestron Plossl alone, i.e. with half number of elements.
I was waiting for the Saturn, it took me the time to write the above paragraphs.
It began to pop into the view at 22:00, the ring opened nicely at a large angle. But I couldn't see the Cassini division, I could at best, say that I could barely detect it. However, I would try to see if I could see it next time. I didn't consider it is success this time.
The little Ranger is more capable than I once think.
This is probably the most fruitful stargazing up to this moment. Among the past sessions, I spent not too many time to explore the night sky when compared to this session. The weather was dewly and the planisphere got soaked very soon. Luckily, the binos served us very well.
Surprisingly, the binos gave me a better chance to look at the night sky. When the sun-set, we first see the bright Jupiter and Saturn. Of course, we could see nothing than the bright satellites and a small disc with the binos. Nothing special for Saturn as well.
As the night moved on, we first looked at the Pleaides and the Orion Nebula. Very good, but they're sort of our old friends. But still, they were impressive. We had a list of new targets tonight.
First, we tried to locate the Polaris. Strange enough, I still couldn't identify this supposed to be easy target after these few years. Maybe it's because I didn't get an EQ mount for my scope, except a very cheap one which had been sold long ago. We soon located the Polaris with the help of the planisphere, and in order to confirm it, we mark its location to see if it moved or not throughout several hours.
We then moved on to look for the Andromeda galaxy. I couldn't locate this one in the last trip which I considered to be a complete failure. I had studied the star atlas for many time to find our way. One of my friends located it first before me. I confirmed from his description that he had found it. Of course, with a hand-held binos, I couldn't share his view. Okay, I tried his method to locate it, and I found it soon. Maybe it's the first time, I found it to be more impressive than the higher praised Orion Nebula!!! We repeated to find it several time and the method my friend proposed was proved to be a nice guide. We extend from the Cassieopia and moved to the direction to a corner star of the Andromeda and somewhere in between, there was a star upper than that straight line, and below that star, we could detect the galaxy.
As the night moved on, we tried to locate the Beehive and it's very nice as well. Other than these new DSOs, we tried to locate some not-had-been identified constellations. It's real nice!
We stopped a while and then we started our trip to the sun raise site. We didn't bring a binos with us, but there're a whole new set of constellations that we could see. And better yet, we proved that Polaris we found was indeed Polaris, since it stayed in its own position after many hours. The bright Venus could be found, but no luck for the Mercury, since there's a bit cloud due east. Not bad, it's a real enjoyable trip.
I switched my target to wait for the Saturn, which is coming. However, the cloud refused to go. Okay, the cloud is still moving. I grasp a view of the Saturn at 120x, not good at all, but it draws old memory.
I better come back tomorrow night.
I could make out four bands tonight. I tried to compare the view through the 6.3mm with 2x Barlows and the 20mm with 5x Powermate. The view through the 6.3mm with 2x Barlows is larger, and the amount of detail in both setting is so similar, and it is not compatible with the result I found yesterday night that the Tele Vue yields a better image.
The Antares yellow filter does help to increase the contrast noticeably, but it also introduces a ghost in the eyepiece. Overall, it's nice to try it out.
I wanted to wait for the Saturn but cloud moved in. But anyway, I decided to wait for a little bit longer.
I have tried to clean the inside of the OTA of the Ranger and some dust was introduced unluckily and after trying several methods, I have successfully removed those dust and it is the first time I used it for observing after cleaning. My cleaning is finally rather successful.
There are many stars when observed with the Ranger, with a 32mm eyepiece. The sky is not dark at all. I would be amazed by the great number of stars before I got the Ranger, but now it is no longer a surprise. Nothing special can be detected, however, when I tried to pump up the magnification on a bright star, I can see the beautiful diffraction pattern, it is steady and nice, perfectly circular. The central solid disc, the first and the second rings are readily observable. What a beautiful sight.
I try to use the Ultrablock also, and it darkens the sky significantly but nothing more can be detected further. There's no magic.
I've made a temporary light shield by wrapping a paper around the objective. Contrast should be improved, since I could see much less stray reflection from the objective side. I've also used a cloth to cover my head during observation to block stray light. However, the light pollution here is just too worst, I could read the star charts without using my own lamp.
Cassini Division was my target, however, only a hint was suspected. By switching among the eyepieces and barlows, I couldn't make it out exactly and confidently. I found it was hard to use averted vision on planets, however, it is easy for the satellite. When I was looking at the planet disc, the satellite (Titan) appeared very clearly; when I looked at it directly, it nearly disappeared. I could see that the ring is rather wide, however, the Cassini Division is still not confirmed. A bit disappointed.
Later in the night, I looked at the Orion Nebula. Before the view was cleared, I looked at the zeta orion. I found that it's a pair of nice double stars, probably my first double star target. The Ranger could split it in 15x and I've tried to push up to 381x and the view was still nice. Good!
The light pollution has affected the whole view of the nebula, and it was quite different then the view in another sub-urban area. The Nebula has become very small, even with the filter and nearly disappeared without the filter. However, by pushing the magnification up to 120x, the view became quite good. When looking at the Nebula at 120x, my attention was caught to the trapezium. I guess it was the first time I really saw the trapezium. Four stars were all visible, and they're covered by the nebula. A very nice view I would say. By pushing it further up to 240x, the field of view became smaller, but not much detail could be seen.
Later for the Saturn, it appeared at around eight O'Clock. I discovered it when I was scanning the little viewing window by using my pair of binoculars and I found a orange small elongated disc. Using the Ranger at 15x confirms the view. I've tried various magnification on the Saturn but not much detail can be seen, just like the Jupiter. I could hardly see its moon, the Titan.
I've tried to use the Orion Ultrablock for both of the planets, since people reported that it could be served as a green filter, I found it not to be the case, maybe the Ranger is too small in aperture. Using the #14 yellow filter could not help to improve the contrast, and however, the light transmission for the filter is high, and I guess it's suitable for my little Ranger. Maybe I should try it later when the sky condition is better.
Tonight, I've also tried to push the scope up to 381x and the image is just a bit too dim to be useful. Actually, even at 240x, the image is not bright enough. I guess 150x or even 120x is optimal.
The window is inside my kitchen, and after setting up everything, I placed a wooden board on the floor to place my eyepieces and barlows. At the first observation, I could see only one barely visible star with my naked eyes. Pointing the Ranger there reveal a pink sky, with a lot of stars, filling the whole field of view of the 32mm. Excellent view! I was attracted, and by scanning around, there were quite a large number of stars available. Turning to the 20mm makes the view of the stars even better for the sky become darker.
In the second observation time, the Saturn suspect appears but after pointing the Ranger there at 15x, I could make a conclusion that I've made it wrong, it's not the Saturn. Instead, I guess it could be the Betelgeuse. Okay, I switched my goal to test my Ranger again. I first pushed it to 381x with the 6.3mm plus the Powermate, the diffraction pattern is not bad, I further push it to 762x, the image is so similar as the 381x, except the star moves so quickly that I could hardly keep it in the field. By placing the 2x barlow before the Powermate, I guess the power is even higher, and yes, the image tends to break down. Anyway, I was pretty disappointed, since I want the Saturn.
Thursday, January 27, 2005
My target tonight was to find the Andromeda Galaxy (M31), since my friend and I were able to spot it in my binoculars in the last trip. I hadn't brought my binoculars this time, which was one of the most important excuse (reasons) that we couldn't find it this time. I guess that it's due to the fact that it's located nearer to the horizon this time. While I were searching for the M31, I found another galaxy which I thought it was the one I wanted. It gave me the feeling for being able to find something, even it's not truely the one I wanted.
Later I looked at the red dot from the Star Pointer, I found the location of M31 should not be that point in the sky. The angular size of the galaxy I found further proved me to be wrong. Looking at the DeepMap 600, I concluded that it was the Pinwheel Galaxy (M33). The sight was good, but it's a bit dim for the 70mm Ranger.
The Pleaides and the Orion Nebula were superb in the Tele Vue zoom. I don't quite affected by the narrower field of view at low magnification of the zoom. Maybe it's because I has not been "spoiled" by the wider-field eyepieces, yet. The view of Jupiter and Saturn were very good as well, at least not a bit poorer than my 20mm Tele Vue Plossl. The zoom capability was really convenient and also useful. Once the target was found, I could zoom in-and-out until I found the optimal magnification. Since clouds moved in occassionally, I found I couldn't see the planets long enough to figure out the real performance of the zoom at higher power. I didn't get a chance to use the Powermate as well, but I've a feeling that the 2x Orion Shorty Barlow might be a better couple with the zoom. The 5x Powermate should be a bit too high, at 100x even at the lowest (24mm) setting with the Ranger.
I also got a chance to watch the sun on the next afternoon using the zoom, the view was excellent. That was the first time I watch the sunspots with my scope, several sunspots (at least seven) were easily visible. I could also look the the detail of each of the spots, and they looked circular with smaller spots inside. So, there were actually several sunspot groups available. I had also taken some photographs with my friend's digital camera, and they can be found at my astrophotography page.
In conclusion, I love my zoom and my Ranger, as well as the new solar filter. Oh, yes... and also the new Gitzo G106 tripod, it was very light and compact, make it extremely portable. So, I sold my Manfrotto 055C in the next week. :)
I think I shall draw a short conclusion after about half a year of usage. The Tele Vue zoom becomes my eyepiece of choice if I have to pick one only. At 24mm, the real FoV provided is large enough for me to find my targets with the Ranger. And at 8mm, it provides enough magnification for me to observe even the planets. Of course, I usually bring the 2x Orion Shorty Barlows or the Tele Vue 5x Powermate along with the zoom. To compensate thing a little bit better, I will also bring the 32mm Sirius Plossl.
In a night with excellent seeing, I've the experience to clearly see the Cassini Division with the Tele Vue zoom at around 120x with the 5x Powermate, cloud bands on the Saturn is obvious as well. I've also see the GRS and many many (over 8!) cloud bands on the Jupiter. More importantly, all these were done with a 70mm Tele Vue Ranger! Averted vision is NOT required. However, I've done it in one and only one occasion. You will never know how your telescope performs until the sky is excellent. On deep sky objects, I've also seen the fan shape of the Orion Nebula on the same night, and that's also the first time.
Unluckily, I haven't brought my 20mm Tele Vue Plossl with me that night, or else I can tell how the zoom performs when compared with fixed focal length eyepieces. But I'm sure that the zoom will not be a disappointment.
And to me, it's an amazing piece of art.
5-Oct-2000: Night and 6-Oct-2000 morning
During the Chung-yeung festival, we want wild-camping at Chek-king. Tonight, I've brought with me only two eyepieces. They're the 32mm Sirius Plossl (to provide me with the largest possible FoV) and the new Tele Vue 8-24mm Zoom. I've also taken the 5x Tele Vue Powermate. After the whole night, I found that the 32mm was left alone in my eyepiece case.
The Pleaides and the Orion Nebula were superb in the Tele Vue zoom. I don't quite affected by the narrower field of view at low magnification of the zoom. Maybe it's because I has not been "spoiled" by the wider-field eyepieces, yet. The view of Jupiter and Saturn were very good as well, at least not a bit poorer than my 20mm Tele Vue Plossl. The zoom capability was really convenient and also useful. Once the target was found, I could zoom in-and-out until I found the optimal magnification. Since clouds moved in occassionally, I found I couldn't see the planets long enough to figure out the real performance of the zoom at higher power. I didn't get a chance to use the Powermate as well, but I've a feeling that the 2x Orion Shorty Barlow might be a better couple with the zoom.
The 5x Powermate should be a bit too high, at 100x even at the lowest (24mm) setting with the Ranger.
I also got a chance to watch the sun on the next afternoon using the zoom, the view was excellent. That was the first time I watch the sunspots with my scope, several sunspots (at least seven) were easily visible. I could also look the the detail of each of the spots, and they looked circular with smaller spots inside. So, there were actually several sunspot groups available. I had also taken some photographs with my friend's digital camera, and they can be found at my astrophotography page.
In conclusion, I love my zoom and my Ranger, as well as the new solar filter. Oh, yes... and also the new Gitzo G106 tripod, it was very light and compact, make it extremely portable. So, I sold my Manfrotto 055C in the following week. :)
This is not the first time I observed the Sun, the last time was a brief look by hand holding the Solar Filter on the binoculars, a few sun spots were detected last time. This time, I observed using the Ranger with the Solar Filter. Several sun spots were detected, with a cluster of sun spots somewhere near the edge of the solar disc. I was using the Tele Vue Zoom through my glass windows (!!!). I knew it's bad but it's an unplanned observation inside my apartment. Not bad, still.
13-July-2000: First Day and Night
- day -
I received my Tele Vue Zoom finally this morning. I bought this one from the Pocono Mount Optics, and I have got a Thousand Oaks Type 2+ Solar Filter for my Ranger as well in this order.
I tested the Tele Vue zoom in board day light, and the chromatic abbervation is obvious. This is due to the semi-apochromatic nature of the Ranger more than the Tele Vue zoom, but I've no way to confirm it since the Ranger is my only scope. The eye-relief is very comfortable throughout the whole focal range. The image is sharp edge to edge. The zoom eyepiece at different focal lengths are not parfocal, but they are closed to be so. Careful observation reveals that there's a piece of dust inside, cleaning on the exposed lens surfaces do not help. Too bad that it lies inside the eyepiece which cannot be disassembled easily.
I just hope that it won't be noticeable at night.
- night -
On the same night, I tested the Tele Vue zoom inside my apartment. It's rather cloudy tonight, but the cloud is moving very fast and so there're sometimes that I can observe the stars in-between the gaps. Stars are sharp to the extreme edge, and the dust inside the eyepiece is not detectable at night, luckily. Maybe it will only appear when I observe the moon. Anyway, I would rather leave it alone than to send it back, since it takes too much time. The apparent field of view is stated as 45 degree at 24mm and 55 degree at 8mm, and I would say it's accurate. To me, 45 degree apparent field of view is not restricting for my taste and the 55 degree at 8mm is nice as well, wider than my previous experience on observations. I only got a few plossls, and maybe that's the reason.
When compared with the 20mm Tele Vue Plossl, the field of view is smaller, as expected. The field stop size at its maximum for the zoom is still smaller than the 20mm Plossl. But the difference is small. I randomly look at the sky, and I can see exactly the same number of stars in both eyepieces, implying that advanced coating make the extra-elements not too bad on the zoom. I tried the zoom with the Tele Vue 5x Powermate and the Orion Shorty Barlow (2x), and they work very well.
On zooming, the apparent field of view expands but the actual field of view diminishes. Close stars become farther apart and the sky background becomes darker as the magnification increases. It's so nice that we can choose the optimal magnification without changing eyepieces. And that's the major reason for why I bought this eyepiece. I couldn't detect any real difference between my 20mm Tele Vue Plossl and the zoom. Maybe I should later try the zoom on the planets, the moon and other DSOs.
This was the first time I tried to pack everything (telescope, tripod, eyepieces, barlows, filters, star atlas) into my backpack. It was rather heavy but still managable. Of course, I still want a lighter setup. Anyway, it's an elegant solution already. I made my observation list in the afternoon based mostly on Turn Left on Orion.
Our observing site was bright. I could read the charts without flashlight (but not read the words) and there was a thin layer of cloud above. Not very good, but it was already a great time for me. My observing list included M4, M51, M81, M82, M13, the Double-double, the Ring Nebula, the Albireo and the M27 Dumbbell Nebula.
I tried to make the list shorter, since I knew that I was still learning. The targets should not be too difficult.
Finally, I got only Albireo or to say more accurately, it's my wife who got it. But that was nice enough, we were amazed when looking at this orange-blue (gold-blue) pair!!!
"I need a larger scope", I thought. But I remembered that my equipments were already quite heavy, I told myself, "I need a darker sky!"
Today is 5-July, when I read the s.a.a newsgroup, I confirmed that my wife and I had actually detected M4, the globular cluster near Antares of Scorpius. Originally, I thought it was fogging of the eyepiece, but later I knew it was there, since it moved with the stars as double confirmed with my wife. After reading from the newsgroup (another guy in Singapore is asking the same question, but he's using a 6"), the description is exactly the same. Good!
30 June 2000 By So King Yan Oldfield
I've never spent that much time which the moon. Tonight, the transparency is bad but the seeing is good. Nothing else could be another target except the bright moon, which is now nicely placed in my little viewing window out of my window in my sleeping room. It looks fuzzy with naked eyes.
I've used my Ranger to do the observation, and it's the only scope that I've after I sold my C90. I didn't miss my C90, since it could not show me anything that the Ranger cannot. The eyepieces which I've used include a 20mm Tele Vue Plossl and a 32mm Sirius Plossl. I've the 5x Powermate and a 2x barlow with me. Therefore, I have 15x, 24x, 30x, 48x, 75x, 120x, 150x and 240x, quite complete. For the moon, I use 75x, 120x, 150x and 240x. I've a light yellow filter (#12) with me as well.
At both the 150x and 240x, I find that my eyepieces are dirty. At the very beginning, I suspect those were my floaters in my eyes. By rotating the eyepiece, I know that it's not the problem of my eyes. By rotating the barlow or the Powermate, the dirts do not move as well, that means I have to clean my eyepieces.
After cleaning the eyepieces, the views are so good. At 240x, the moon drifts across the field of view quite fast, together with the craters on the moon surface. I've a feeling that I'm traveling slowly in a space ship, looking out from the windows. At 240x, the field is not too big and I could only keep looking at a few craters at a time. I found the view at 150x much more comfortable. Adding a color filter does increase
I find that most of the craters are nearly perfect circles, and they are not very deep when compared with their diameter. I don't have a moon map and so I cannot identify the craters, but I find it interesting just to look at them. I have a feeling that I am very closed to the moon, the craters look so large. (Yes, I know they're actually much larger)
Even with a standard Plossl, the field of view is wide enough and pleasing, and I wonder how it would be if I looked through a wide angle eyepiece. Anyway, it's a matter of emotional feeling rather than it is much more useful.
I find that the thin layer of cloud is a not too bad filter. It softens the image produced, but there are still many surface features visible. It darkens the glare even without my own filter, so it comes for free. I find that the moon is too bright even with a small exit pupul, at 240x, i.e. 0.29mm. And since it is so bright, it is a pretty good target for small scopes.
I switched to 75x finally, and the moon fits nicely in the whole field of view. With the Powermate, the 32mm Sirius Plossl produces sharp image across the whole field of view. The edge performance of the Sirius Plossl is not so good without any barlow. The most suitable magnifications are 120x and 150x for the moon, I think. I prefer to
use the 75x for the eye-relief is slightly more comfortable than that of the 120x. I can see the whole field of view in both setting.
Next time, I should come back with a moon map.