Various Accessories for Sales

Package deal: $999 HKD takes them all! 

More items added but price reduced. (18 Nov 2011 update AGAIN) (21 Nov 2011 three more items and the same price)


Or name your price, reasonable offer will be entertained, just don't want to waste all these stuff.

First up is a 70mm doublet (f=500mm) mounted and with 77mm thread, suitable for macro imaging which brings the closest focusing distance down to less than 500mm. Ask for $200 HKD.

Astrotech 1.25" dielectric diagonal in great condition, flawless mirror and with the original box, ask for $350 HKD.

Generic small Chinese ballhead, suitable for digital camera, ask for $50 HKD. (RESERVED for CL Chan)

Shoestring FCUSB, virtually new never used in the field, ask for $500 HKD. Control and power your JMI focuser via your USB port.  Ask for $500 HKD.

Celestron Nexstar mount parts, including both motors with encoders, also the gears.

Ask for $400 HKD, the motors alone should cost more than that.  And I got the following information from a CN buddy:

"These were used on the original Nexstar 5 and 8. The 5 and 8i used Lo-Cog Pittmans with different encoders. These things are available for about $275 each new.

The same early motor was used on the classic Meade LX200 16", although the gear reduction was 19.5:1. I was able to find a recent series 8000 Lo-Cog on eBay with the correct gear ratio and swap the gear heads to get the 19.5:1 ratio.

The Meade used a different encoder count too, so the HEDS encoder and the code wheel have to be swapped to use it on the LX200."

Motors were SOLD, gears were still available at $50 HKD.

Sealed Lead Action battery, reliable power solution in the field. Comes with a Panasonic 12V 7.5Ah SLA battery, a charger which will take 12V or 6V SLA, and also a generic notebook transformer which offers 15-24V by using the 12V SLA.  Ask for $100 HKD for all three!

You will one day want this tool, it's for creating threads and threaded holes yourself. Virtually new and ask for $50 HKD only (RESERVED for Simon).

JMI 2" -> 1.25" compression ring adapter:-

DIY 43mm male thread afocal imaging adapter:-

Never used JJC EC-2 Eyepiece Extender for Canon EOS DSLR:-

Another custom machined 2" to 1.25" adapter, it's pretty heavy and could be good for balancing light weight 1.25" eyepiece and heavier 2" eyepiece. With two locking screws for added security.

Originally for my Gitzo G1415 when I lost one of the spikes on the legs, so I still have two remain. I've sold my G1415 and now they're sitting idle... very hard to find in Hong Kong and even the distributor refused to order them for me. Ask for $200 HKD.

A small 7-14x monocular, good quality for this size.

The Quest for a motor for my Mark-X

2011-11-18

The motor arrived in perfect condition, however, the shaft coupler is missing and thus I will probably need to buy one myself.  On the other hand, I'm delighted to see its quality, the buttons were very nice to press and the pin on the connector to the hand controller is just thick and strong!  I'll need to built a power supply for it, and the seller reminds me that it's center negative and it's running at 9V, and thus a 8AA rechargeable will be about right!

After verifying that the motor is indeed working, I shall find a suitable shaft coupler for it and also how to mount it to the Mark-X, finally, I will need to find a replacement crystal oscillator for 126 teeth.

2011-11-13

While waiting for the delivery, I've searched some potential oscillator suppliers:

Mouser, I ordered from them before, trouble free and good range of stuff

http://hk.mouser.com/Home.aspx

RS Online

http://hongkong02.rs-online.com/web/

2011-11-09

The motor and controller is now on its way to me, tracking number: LC308020755US

The seller was kind enough to tell me that the controller is center negative!  I should keep that in mind.  The first thing which I'm going to do is to put it on the mount, I guess that the shaft coupler will connect without big problem.  I shall see if the torque is enough and if I will need to improve the mounting stability, and maybe I will need a local machinist friend to help here.

Secondly, I will need to open up the controller to see how can I modify it from 180 to 126 teeth, I wish and I expect that it will be controlled by a crystal and than I can scale the frequency and buy a new one for it.  Exact matching might not be possible but I hope that it will be close enough for me to track like 5-10 minutes at, maybe say, 200mm focal length.

Found a scanned specification sheet of the motor/controller.  It has a part number of RMD-2401 and also a model number of CXD-1.  In the specification part, it was described as quartz stepping motor and thus I would probably be able to swap the quartz crystal in order to adapt it to 126 teeth.  The rated voltage is 9V and the allowance is from 4.5V to 12V.  It consumed 160mA and it supports clockwise, counter-clockwise, 4 times speed, and also temporary stop.

From the limited photographs, I believe it would be very easy to mount it to my Mark-X.

2011-11-08

I'll try to buy a Japanese Carton mount motor and attempt to modify it myself.  It's the same motor for the Tele Vue system mount which has 180 teeth, since it's a very old model, and I suppose that it will be controlled by crystal and thus, the modification should be relatively simpler for me since I don't need a EPROM writer.  Of course, matching crystal is another hard story and an exact match is probably impossible but for tracking like several minutes should be perfectly okay, at least I tend to believe so.  Let's see if I can get a good deal.

2011-11-05

There're some very cheap RA motor selling in ebay but the seller never response my request for shipping quote.  Not until I click buy-it-now, and then after a few days, I managed to get the shipping but it's 2x of the motor itself!  Of course, I will have to cancel it.

2011-11-03

If I were to use gear pairs to match the gear ratio, maybe I should use a off-the-shelf motor with controller rather than to build everything from ground up by myself?  At least it seems more reliable?

2011-11-02

I've two existing DC geared motor, it's rated at 5 RPM at 12V.

Tonight, I've tried to apply 2.4V DC to it and it runs, I did a very rough estimate and it's running at 1 RPM at 2.4V... Suppose that I have to get 0.0875 RPM, I will need to slow it down further by using a PWM controller first, and then I will be able to get 0.1 RPM.

To get 0.0875 RPM, I will need a pair of gear, for examples, 28 and 32 tooth gears as recommended by DAVIDG in cloudynight atm forum.


I've to check my existing gear inventory, and see what I should buy. 


I've a 35 tooth gear suitable for the motor, so I will need a 40 tooth gear for the worm gear shaft?


I've another 37 tooth gear suitable for the motor, so I will need a 42 tooth gear for the worm gear shaft?

20111031 Moon

I'm not interested to shoot the sun until I got a better filter.  When the sky was getting darker, I saw the bright moon hanging out the window, so why not?

I pulled out my Ranger, set it up on the GOTO Mark-X to take some snapshots.  I'm still searching for a suitable motor for it but at the time being, I can still do manual tracking.

I was using my Lumenera LU070M with my Tele Vue 5x Powermate.

First shot was taken at 1833 (GMT+8):-

And then the second one was at 1834 (GMT+8):-

You know, it's just bad!

Jogging under the starry night again

Went out for jogging as usual, the sky was foggy these days mostly due to air pollutant.  However, the sky was pretty black up there near the zenith.  Jupiter was hanging up there, shinning as one of the few "stars" in the sky.

Guess what, I immediately think of my newly acquired GOTO Mark-X.  My friend has promised to hack one from a EQ3-2 motor for me, but I've got no update since then.  I know that I could not rush and I should wait patiently until I got a phone call one day.

During the wait, I could still use manual tracking and I could still think more about how the mounting plate should be made.  The simplest design would be a simple slow motion control which allows me to rotate the scope like the DEC axis of any German Equatorial Mount, and the other side would be a ball head which I already had.  It would allow high power imaging and probably manual or webcam assisted guiding at the same time, and the ball head side would also allow wide field imaging.

I believe that I won't go for a counter weight unless I've something bigger, a movable 5 * AA battery pack should be used for assisting balancing. 

Time to sell that brass counter weight as well?

Now, my miscellaneous sales should include:

1. Shoestring FCUSB
2. Astrotech 1.25" dielectric diagonal
3. Bass counter weight
4. DIY 77mm macro adapter or 70mm f=500mm doublet
5. Small Chinese ball head
6. Metric threading tool set
7. Lumenera LU070M
8. DIY Mark-X mounting plate and counter weight system
9. 5.5" tube ring set

Tell me if you're interested of any of the above items.

20111019 Sun

Seeing 2/10, transparency 3/10, moving cloud.

Thousand Oaks Type 2+ (full of pinholes), Ranger, Lumenera LU070M, tracked manually with GOTO Mark-X.

From the right side first, the bottom dark one is AR1314, and the bigger group in the middle is AR1319.  On the other side that large pale patch AR1323 and 1324.

This is the first time that I use the new Generic Chinese ballhead for imaging, it's strong enough but it's not very good for fine adjustment with high power (480mm * 5 = 2400mm) and I assume that I will need a fine adjustment head like Manfrotto 410 before it could be used for high power imaging.  However, my 410 is now serving as the polar alignment wedge.

That ball head is strong enough with my Ranger even at high power, no shifting noticed.

For wide field imaging, I don't have to go anything stronger.  For planet imaging, I will need another head but then now I just have my Ranger, no need to concern about high power at the time being?

Features of the Mark-X mounting plate

Before I make the drawing, I shall write down what I wanted:

1. Light weight and short
2. Able to balance for two equipments of different weight
3. Able to take two (ball) heads
4. Able to attach a mobile phone to aid initial polar alignment
5. Able to mount a battery pack on one end for balancing (e.g. 5 AA rechargeable)

Feature (4) and (5) could be done in an ad hoc manner, not necessarily a design time feature.

Anything else?  Here's the first draft:

--

19/Oct:

1) Found a 5 * AA battery box, it could be used to provide 6V DC required by the motor, and therefore, this battery box should be fixed on one of the sides.

2) Should also prepare a way to mount a counter weight shaft there in case I wanted later

3) Or buy something like this:

http://item.taobao.com/item.htm?id=8277650748

cut the upper part and attach to one side of the plate?  It will then allow slow motion control.

A trial run of the Mark-X

We have some sunshine but we have even more cloud.  It would not allow good images but it would not stop me from trying out hand tracking with the Mark-X.

This is the setup.  The hand tracking knob is very nice, and it's long enough to be controlled by me with another hand on clicking the computer for which the LU070M is driven, hand tracking is easy and smooth and it's definitely good enough for solar or lunar imaging.  Planet imaging could be more challenging but then I believe it's also doable.

It's a bit ridiculous that I've a motorized focuser but not a motorized mount.  Anyway, I kept the NGF-CM mostly for its 2" capability rather than its motor.

I didn't even open the window mill since I don't think I can capture any good image under this sky condition.  Here's the result anyway, and the sun is full of activities!

It's a pity that I don't have an H-alpha filter with me now, not even a good white light filter.  Anyway, I will enjoy whatever I have on hand.

Conclusion of priority:

1. I will buy a good ball head first so that I can use this mount by manual tracking first.
2. Motor will be next, hacking the motor controller will be even later.
3. Mounting plate final, not until everything is ready.

Polarscope of GOTO Mark-X

Today I set it up to test whether the polarscope was properly aligned, and if not, I've to adjust it during day time.

I look through the polarscope to distant objects and found that it's matte.

I pointed the polarscope to the corner of a building and then I begin to rotate the RA axis.  It's very smooth and it's a joy to turn it.  Obviously, the polarscope is still in great alignment with its axis, there's no obvious moment.

This is workmanship!

Trying out the GOTO Mark-X

Just put everything on that heavy DIY plate, and it's just a piece of cake for this robust mount.

I cleaned the GOTO Mark-X last night and it looks very fine now.

I've attached a small ball head and a small pan plate to that heavy DIY mounting plate to see how the whole thing works.

Even when the mount is not balance like this, it moves very smoothly.  I'm very impressed and really longing to have a motor for it!

GOTO Mark-X

This is a real Japanese classic.  Thank God that I can get one for myself. 

The original owner has a DIY counter weight and mounting system for it as shown below.  However, it is probably too heavy for me, and so I should go for something else later.  I will need to design a simpler and lighter mounting plate for it so that I can attach a ball head to it, and maybe a guide scope on the other side.

After assembling, and they were put on my small Gitzo G106 tripod with Manfrotto 410 head, that DIY setup is really very robust and heavy.  I guess it will take a C8 without any problem! 

And finally, this is the most important part, the GOTO Mark-X.  The slow motion control knob is very nice, and you will feel the quality when you turn it with your finger.  This mount is over 20 years old but then it's still functioning great!  Smooth like cutting through butter.

I say goodbye to my Takahashi TG-SP II on the same day, and the GOTO Mark-X is acquired through partial trade.

The first thing that I will need to do is to find someone who is willing to adapt a EQ3-2 motor on it for me, the hardest part is to make it compatible with 126 teeth. I don't have the equipments to do it myself.

And then I should probably live with that DIY mounting plate first.  Yes, it's heavy but then I should test it first with a ball head which again I may have to buy.  I expect the motor plus the ball head would mean over 1K HKD, and I will probably need one more ball head, a polar scope illuminator, and a lighter custom made mounting plate in the long run.  But I will keep it simple and stupid at the time being, and maybe even do manual tracking first!

The Sun Remains

Yes, the sun really remains unchange but I no longer have my solar filter. Even my Thousands Oaks white light is now full of pin-holes.

20110919 Sun

2011-09-19 14:22 (GMT+8):-

Again with my Thousand Oaks filter but this time not using a telescope nor a Lumenera but my Canon 450D + Kenko 2x + Canon 100-400mm at 800mm effective focal length, five frames stacked and processed...

The sun should be very active these days but my aging white light filter couldn't reveal much of its detail.

20110913 Sun

AR1289

AR1295

Both taken with my Tele Vue Ranger, Thosuand Oaks Type 2+ Glass (full of pin holes!), and also a generic green filter, Tele Vue 5x Powermate, Lumenera Lu070M.

No tracking, I just count on the fast frame rate of the Lumenera.

FS: Takahashi TG-SP II (SOLD)

Seldom used Takahashi TG-SP II (less than 10 times in the field), tracking mount for small telescopes and DSLR with lens Original Counter weight, hand controller, battery case, V-bracket for Hong Kong, polarscope with paper box Additional stuff: German made GP compatible dovetail saddle, bass counter weight, 4AA battery box, USB power cable, plastic case to keep everything inside, ask for SOLD HKD. I should have the original paper box (not photographed)

And if you want a Russian made dovetail, add $300 HKD.  It has 1/4" screw for mounting telephoto lens or camera.

SOLD

20110912 Sun

Got some sunshine today, I pulled out my Thousand Oaks to take a few snapshots.  My JMI NGF-CM controller was running out of battery and luckily, I still got my FCUSB around so that I can drive the focusing motor through my PC.

AR1289 takes the center of the stage, with AR1290 scattered into two smaller fragments on top of it... AR1287 was on the far right top corner.

Close up by using a 5x Powermate reveals nothing but dust on the CCD, they were left as tracks...

Without any serious equipments around, all I could do now is to do whatever I can.

Some of my earliest shots

I've been organizing the files inside my hard drive, and I found a few astrophotographs which I had made long ago... it was taken afocally through my Ranger, by using a DC of my friend.

Guess what?  The first one should be Jupiter out of focus, the exposure was about right!  The shaky hand and tripod worked together to form this nice image!

And this one should be Saturn!  The power was oh-so-low such that the ring couldn't be resolved.

By checking the EXIF, I know that the DC was a FinePix 40i, taken at 2001/2/20

20110824 Sun

After selling my Solarmax, I have stopped solar imaging for pretty long since now I only have a 10+ years old Thousand Oaks Type 2+. You know, I've been spoiled by H-alpha imaging, CaK imaging and even for white light, I used to do with a Herschel wedge! Anyway, our target is always more important than equipments, and so I pulled out my decade old filter, together with a green filter, as well as my Lumenera Lu070M for imaging.

The telescope used was the Ranger, and now it works with all its 70mm aperture.

At prime focus, i.e. 480mm focal length, 1520 (GMT+8):-


With 2x barlows, i.e. 960mm focal length, 1521 (GMT+8), AR1271:-


Not bad, right? I guess I will continue my solar imaging hobby with this cheap and simple filter.

Sweden Sky

I've a trip to Sweden with my family earlier this month. I was thinking that I might have some chance to take some good starry skies, but then I missed the fact that there's nearly no dark night in summer for places that high in latitude:

For example, at around 10:30p at night, it looks like this:-


Even when it's 1:30am, it's still blue... exposure like 10 seconds will saturate the whole frame.

A Photograph in the Hong Kong Cultural Center

This is an event at the end of 2010, it marks an end to life of my solar imaging virtually. This is a joint event of Hong Kong Birding Society and Hong Kong Astronomical Society:

Trip to Shek O with friends

Planned to go on Friday but the weather forecast was unfavorable, so we switched immediately to go out last night (2011 July 27). Since we're committed to eat our dinner with our own families, we went only until after 8:30pm.

This is the group which I used to observe, they're my hiking friends, my wild camping friends and they're my great brothers in the church. We didn't go out observing together for many years since we have kids at home. After selling most of my equipments recently, I am now using around the same set of equipments like when we first went out observing! So it's a memorial moment indeed.

I didn't bring my camera and tracking mount since I wanted a lighter load despite one of the observing buddies will drive us there. I hurt my foot a little bit when traveling to Sweden so I needed to avoid further injury.

Observing is always fun with friends. We hunted so many deep sky objects under an exceptionally good sky (in Hong Kong standard) when the Milky Way stretched over 90 degrees! It's very rare in Hong Kong these days. It's one of the best skies which I've seen in Hong Kong.

We found all our good old "friends" (observing targets) and we enjoyed sharing the view and of course, the way of finding them. Describing a target is a good way to observe more. Ten years ago, we were using star charts but these days, we have our Android phone and IPad for immediate reference and confirming the targets with the help of various detectors inside these modern mobile phones.

About the equipments:

We have a set of 15x70 and also my Canon 10x30 IS, frankly speaking, I prefer the view of my 10x30 IS for it's just much sharper but not much dimmer. IS is very helpful indeed and I felt in love with it especially with it's huge portability.

The Ranger is still in great shape! In such a dark sky, we could resolve quite many clusters and we could detect any Messier objects that could be found in our charts. Upgrading it by adapting it to a 2" focuser is a great move and now I know why the Pronto was so popular! My NGF-CM works well with the heavy Pentax 40mm XL, and the Pentax is very comfortable with eye glasses or without. It yields over 5.4 degrees of view and it's even wider than all binoculars that we had.

This was the first time that I was really using my 13mm Nagler on deep sky objects and it's again exceptional. I won't sell it without a great reason. Pushing the power from 40mm (12x) to 13mm (37x) is pretty dramatic! The sky was darkened further and the stars were better resolved, some brighter faint fuzzy was rendered with detail to our eyes.

We spent most of the time with the Messier objects around Scorpius and Sagittarius... we visited the Coat Hanger and also we waited for M31 just because we visited it years before.

Visual observation is nice for it's just so simple and fast to pack up all the stuff after around 3 hours of observation.

--

Some further remarks in Chinese (Cantonese):

今次行程超滿足, 也帶來許多舊回憶和舊感覺，我們大概已經十年沒有再特地出去觀星。沿路走入石澳山仔 (大頭洲)，海浪聲和那條山路都很不錯，有一點行夜山的感覺呢！

今時今日我只剩下一支 70mm 望遠鏡，和一支 Canon 10x30 IS 雙筒，這正好跟十年前差不多。不過，現在我那支 70mm 卻可以上 2" 目鏡，這叫它比雙筒更廣闊更好用，我亦多了一只 13mm Nagler，中低倍的表現實在驚人！這目鏡配合 Ranger 實在最好不過。

石澳昨晚的天色很好，銀河清淅可見，應該有超過 90 度，是我有史以來在香港看過最好的銀河！如果進行拍攝，效果應該不錯呢！但因為我上星期扭傷了腳，所以不宜帶太重的儀器，結果還是打消了念頭。後來發現這倒算不錯，因為我們可以花更多時間來觀測，不然只是短短三數小時，恐怕我也只能拍幾張相片而已！

完結時，阿茂竟然拿出幾罐凍飲，叫我實在感動不已！熱天觀星最可惡就是汗水和蚊子，喝一口冰凍的氣水實在值千金。以往觀星受公共交通的班次所限，不能太夜回家，今次阿茂揸車，節省了不少時間，也可以延長觀星時間，真係無得頂。

下次或者都係要影埋相先得！

感激志光哥第日要返工都陪我地出去，又多謝阿茂既車出車入與預備，更要感謝天父預備好天氣，叫我地可以舊地重遊，更與天上的老友重逢 :-)

A Simple Night with the Starry Sky

I have been reducing my equipments since now I know what I love to do and what I want to do. The sky is very nice these days and so I picked up my stuff and went for a short observation session.

My destination is Pak Tam Chung, not exactly a dark site but it's readily accessible with or even without a private car. By public transportation, I got there at around 1 hour and another hour for coming back, with a total cost of $40 HKD.

I packed everything inside my Fastpack 350 basically. I've my Takahashi TG-SP II, my 450D together with a Samyang 8mm f3.5 and a 50mm f1.8. I didn't bring a lot of lenses since I want to relax and enjoy! Other than that, I placed my Gitzo G106 in a small bag and carry it along side. Oh yes, I also have a couple of star atlas and also my Canon 10x30 IS for visual observation and scanning.

Polar alignment the TG-SP II is not very easy but it does not require great accuracy since I will only use a 50mm lens or a fisheye. That little polar scope works even with one of the cables plugged in, if you plug it both, the objective is obstructed by too much so that you cannot even see Polaris.

Here're the results basically, with a 50mm f1.8 lens, four shots stacked:-


Taken with the fisheye, while the sky was not yet dark, 4 shots stacked. Using a fisheye is harder than imagine in Hong Kong, you will have aeroplane in each shot basically, and you will to keep exposure short and you need luck!


Another one taken with the fisheye, I've to skip a few shots to avoid the aeroplane tracks:-



A picture of myself in front of the fisheye:-


An accidental Iridium flare.

The bus station is just 2 minutes away, I was the only one on the bus in the return trip.

Finally, the Samyang 8mm f3.5 was quite nice, stop it down by one-stop (f5.6 in the next click stop, so it's more than one stop), and stars were basically pinpoint. No focusing required with the huge depth of field, you can trust that infinity mark since the tolerance is huge.

I did scan the milkyway and the whole sky especially the Scorpius area. I didn't check my star charts since I just want to relax, and I just point to what I can remember, and also to scan around like a kid for anything interesting.

This is a convenient place such that kids could go without problem, guess what, I arrived home at 10:00pm... I started packing up my stuff at 9:00pm, and next time, I can pack at 9:05pm or even 9:10pm and I still won't miss the bus.

Skeye for Android

I'm still using my old fashion WM6 mobile phone but my wife has a new Android mobile.

I just found that there's a free application called Skeye which can show the sky with labels like Google Sky Map, and better yet, there is a aiming circle for this application and it's even built with the concept of DSC (Digital Setting Circle) in mind!

To fix it on the OTA, I've seen in youtube that people made brackets specially for it. And now since I only have a small refractor, I'm thinking that a simple sport armband would work, and it's going to be neat and tidy!

The Samyang 8mm f3.5 arrived!

I've some paypal balance and I consider it better to buy something than to transfer it to the bank since the charge is high and the conversion rate is bad.

I ordered it last Thursday and it arrives today (Tuesday), so it's very quick. The seller does not give me a tracking number and I could find one on the package, so if they will send it to me, it's definitely better.

The items were well packed, but the lens cleaning set has some of its fluid leaked maybe due to the pressure from other items. The box of the kit was partially soaked and some of the papers inside the box was somewhat wet as well, luckily, the lens was not affected at all.

The brand name on the box was Rokinon but the manual has Samyang, so it's an OEM product. The lens was built like tank with tight tolerance. The focusing ring was smooth and the aperture ring snaps into place with clicks. Focusing was easy due to its huge depth-of-field even at f3.5. No focusing was required if I stick at f8 or something like that. The focuser is butter smooth, a feeling of high quality focuser, feel like L class lens. No joking!

The metering of my 450D tends to give brighter image, but then I found similar issue even with my telescopes attached. Simple exposure compensation (AV) could fix the problem easily.

I never played with such a wide lens and 10mm is the widest I tried. The huge field of view and the fish-eye effect was immense! I guess that I will need to spend a lot of time with it to get use to it. The first thing that I wanted to do was definitely a wide field imaging on a good starry night but then since a typhoon is coming, I will not have a chance to do so any time soon.

Observing with the kids

The plan is simple, the kids wanted to see the Saturn! Therefore, we don't have to travel but we can truly grab-and-go! I've my Ranger on Gitzo G106 with Manfrotto 410, I also have a 40mm Pentax SMC XL as a finder (over 5 degrees of view) and a 20mm Widescan (24x) and also a 5x Powermate (120x).

I was soon misled by Arcturus which is similar in coloration! Without much sky to deal with, I swing my Ranger around to point at Arcturus thinking that it was Saturn... it's nearly the zenith and thus I had a hard time to locate it. After fooling around for nearly 5 minutes, I managed to get it into the view... you know, using a 410 head suffered from the Dobsonian hole issue for target near the zenith. Got it but then it's nothing but a star!

Being cheated, I asked my sister to use her mobile phone to locate Saturn... we were surprised to see that it was partly hidden by the bright spotlights of a nearby building! I swing my Ranger there, immediately blinded by the spotlight but still, it's not hard to point at the Saturn. Pushing the power to 120x, the view was not affected at all.

The kids took turn to look into the eyepiece. I guess some managed to see, but some with doubt. I guess I should keep an easier eyepiece for the kid, like a cheap Plossl, since Widescan or even Nagler could be quite hard to look through due to their sweet-spot and blackout issue. However, the wider field of view should be nice for a non-tracked mount.

20110619 Saturn

Last time I was capturing Saturn with a fixed tripod, this time, I used my TG-SP II in the hope to capture a longer AVI or even push the image scale further.

First of all, I setup everything with my Pentax SMC XL 40mm in place. I found the setup is too heavy for the original counter weight, so I've used the heavier local made counter weight and it tracks very nicely.

Saturn was barely non-stellar in this low magnification (12x). I balanced mount roughly and then I proceed to a 20mm Widescan since it's roughly parfocal with my Lumenera. With the visual view, I couldn't see any problem on the balancing but I doubt when it comes to imaging. Then I added my 5x Powermate into the optical chain and I soon realized the issue on balancing! The mount was not tracking well and the slow motion control was not working very well, either.

Since I don't want to re-balance everything, I replace the Widescan with my Lumenera and with some major effort, I finally managed to fit Saturn into the view but then I found it drifting like without tracking. I also found that this setup was a little bit too heavy for my Gitzo G106, maybe since I've a 410 head and a Takahashi wedge so that the center of gravity was higher than usual.

It's a failed attempt.

Anyway, I've still capture two clips, and the first one was at 7.5fps (i.e. 1/8s with medium gain) and the second one was at 15fps (i.e. 1/15s with high gain).

2158 (GMT+8) at 7.5fps:-


2159 (GMT+8) at 15fps:-


The lower power visual setup with Pentax SMC XL 40mm:-


The imaging setup:-


Note the large weight difference!

Inventory Checking

I did something similar on November 10, 2010.

Telescopes/Objectives:

1. 70mm f=500mm achromatic objective mounted with 77mm thread
2. Tele Vue Ranger
3. Canon 10x30 IS

(1) is for sales at $300 HKD, useful as a great closeup lens for camera lens!

Eyepieces, Barlows and Diagonals:

1. Pentax 40mm SMC XL
2. Tele Vue Nagler 13mm Type 6
3. Tele Vue Powermate 5x and 2x Barlows
4. Japanese Widescan Type III 20mm
5. Japanese Ortho 7mm
6. Tele Vue 1.25" mirror diagonal
7. Chinese 2" mirror diagonal
8. Astrotech 1.25" dielectric diagonal

(8) is for sales, it's very new with box, $500 HKD.

Mount/Tripod:

1. Gitzo G106
2. Manfrotto 410
3. Takahashi TG-SP II

Camera and accessories:

1. Lumenera LU070M
2. JMI NGF-CM with Tele Vue Ranger adapter
3. Thousands Oak Type II+ for Ranger

(1) is available for sales, $2700 HKD.

20110616 Total Lunar Eclipse

Woke up at 2:00am, the mount was already there in place, just need to put on the camera and it's done.



The above is my equipments: Canon 100-400mm f4.5-5.6L with Canon 450D, a timer release cable is attached and a USB cable was also attached for downloading images for Facebook update. The timer release is not very useful since the moon was blocked for most of the time. Takahashi TG-SP II was used for tracking and it's powered by the USB port of my PC through a DIY cable, it's just convenient! No need transformer, no need to charge any battery, etc! The whole setup was placed on my Gitzo G106 with a Manfrotto 410 head to fine tune the polar alignment.

I also have my Canon 10x30 IS for visual observation, I did something similar during the total solar eclipse in 2008 and I can observe with my right hand holding the binoculars and my left hand to press the shutter release.

While setting up my Canon 100-400mm, I took my 200mm f2.8 to have some handheld snapshots first since the cloud was getting in.



When the tracked setup is ready, things are much better. As the moon gets dimmer, we will need some form of tracking since you're doing several seconds of exposure. Originally I planned to do 800mm with a 2x Kenko but then the sky was very bad with thin cloud, so f/11 would be too much!



Cloud was moving around, thick and thin, large and small...



The cloud amount was increasing overall, so some cloud breaks could be as short as several seconds, so you will have to adjust the mount, etc. Spot metering was used, and so you will want the bright part of the moon to be at the center of the frame!



Friends from local amateurs were reporting their situations and some reported rain!



The weather conditions seemed highly localized, and later we found that we could observe far more in some lucky locations!



This is the last one that I managed to capture.



I waited more than one hour after this shot and we had heavy rain and wind.

Finally, I found the moon could be blocked by distant building before I packed up my stuff.

Believe it or not, this is the first total lunar eclipse that I managed to observe, but then I still couldn't see the real totality. Good me luck next time in December if I managed to catch a chance!

Tele Vue Ranger with NGF-CM

I've ordered a 2" filter thread extension tube for my 2" diagonal so that it could serve as a mini-drawtube which effectively extends the focus travel range of my transformed Ranger which has the original focuser removed and replaced with a short focus travel NGF-CM. Such a combination works with all my existing eyepieces from a 2" Pentax SMC XL to a 13mm Nagler with 2x or even 5x.

Previously my Ranger was used solely for solar imaging and since I used it with a reducer, so I really cared more on the in-travel. Now, it's my only telescope so I wanted to make it more versatile.

Now it's also capable for visual work!

Jogging under the stars!

Last night I went jogging at night as usual. In Hong Kong, you really couldn't jog under a lot of stars, but when the sky was clear, you could see some brighter constellations. It's refreshing enough to run, and the stars drift slowly along with time and so you know life is moving :-)

20110612 Moon

After the short and brief pass-by of a small typhoon, the sky was cleared except a thin layer of mist. The moon shines through the windows, casting shadow on the floor.

I picked out my Canon 450D, 100-400mm and a 2x to have some very brief observation and imaging on tripod. The moon was too dim (the mist was too thick!), so that exposure for the moon would be over 3s!

Anyway, the view through the finder is fine enough.