Celestron C5 OTA

This could become harder and harder to come by.

What I got ia s silver tube C5 OTA with Starbright Coating, it comes with a Meade 2" SCT mirror diagonal with 1.25" compression ring adapter. A 9mm Kellner eyepiece is included. The diagonal has a "Japan" label on it, and that 1.25" adapter has a compression ring inside, not bad it seems.


The focusing knob is a bit tight and it has some rough points throughout the whole travel, but then when I loosen the screws a little bit, the problem is gone.


This is the worst part, as you can see from this photograph, part of the rubber ring around the secondary cell is missing. It indicates that the corrector was once removed from the tube for some unknown reason.

I guess that I've got a good deal but then I found many issues with this OTA. The most serious one is that the retaining ring on the corrector is pretty loose so that the corrector can rotate around the cell, bad thing indeed! You need critical alignment for the corrector and the primary!

I've decided to return this scope to the seller. Just waste money for the shipping, sad.

What's still good for this particular transaction is that, I managed to try this OTA on my iOptron and I found that it could handle it without any problem! So, maybe I can go to search for another C5 in the future?

--

I've been struggling for the refund and it's more complicated than I once thought. When the package arrived the seller, he still refused to refund me but he said that the package was damaged during shipping. However, as I found that he has signed to accept the package and that means, the package should be free from trouble as from the outside packing. After the postman left, it's actually hard to tell whether the scope was broken during shipping or intentionally done by the receiving party. Frankly, that scope is unuseable in the first place and therefore, it has zero value and thus, it's impossible to claim any insurance indeed. It feels like you're sending a junk but then you said it's "damaged" and ask for compensation! I believe that it's more like cheating and so I've refused this request promptly and asked ebay customer support for help.

ebay is fast and reliable, I got my refund this morning. Despite I've lost some money for the return shipment, I feel good about ebay who stands behind the deal.

A Heliocentric Birthday Greeting

Among so many birthday greetings which I've received a few days ago, the following is the most astronomical:

"Congratulations on another trip around the Sun!"

And this is actually the underlying physical meaning of a birthday. We will usually take the biological one, but this astronomical/physical meaning could be a nice alternative for amateur astronomers.

20110108 Sun

Some real nice activities... seeing 4/10, transparency 3/10. AR1140 and 1142, with some long QRFs.

1226 (GMT+8), with reducer:-


1229 (GMT+8), with 2x barlows:-


1231 (GMT+8), with 2x barlows:-


1232 (GMT+8), with 2x barlows:-

20110107 Avian Occultatons of the Setting Sun

This event is highly predictable since the last time I visited that site by random during the last partial solar eclipse. It's pretty close to my home and thus easily accessible to me.

I don't know what's the reason behind when then when it's about sunset, the birds will come from nearly all directions! Those birds were mostly not there even 20 minutes ago!

Anyway, it's a nice view.

20110101 Sun

Happy new year!

The sun greets us with a little bit more activity, wish that we have a strong sun in 2011! Seeing 3/10, transparency 5/10.

1223 (GMT+8):-


I'll still use my good old Solarmax 40 with BF10 until it was sold one day.

Selling Solarmax 40 with BF10

I'm trying to see if I can sell it. What's included:

1. the original case
2. Solarmax 40
3. BF10
4. a 1.25" reducer for BF10 ($99 value!)
5. Machined and black anodized adapter for Tele Vue Ranger (77mm thread)
6. Airmail shipping with tracking number to the US or similar destination

If you're wondering why I'm selling it, I would say that I'm looking for an upgrade.

I'm the second owner of this wonderful little filter and I guess that I've owned it for over 3 years and it's still going strong as you can see from this blog. To me equipments are to look through but not look at.

Price $800 USD, no paypal fee. Photographs below:-

Solarmax 40 and BF10:-


BF10 on the red side, also the reducer, the 1.25" filter thread extension tube on the left of the reducer is not included in this deal:-


BF10 on its blue/green side:-


Solarmax on the front:-

20101231 Sun

Solar imaging is so addicting in the sense that you can always observe differences, and you can nearly always shoot when the weather allows, and you don't have to go to any dark site, you can do it in your home, and you can do it only with a short period of time.

Very bad seeing 3/10, transparency 3/10.

1401 (GMT+8):-


1402 (GMT+8):-


Poor seeing messed up any fine detail.

20101230 Sun

The sun continues to shine with low activity, not much change except that large prominence was shrinking.

Two low power shots with reducer:

1520 (GMT+8):-


1521 (GMT+8):-


Higher power shots with 2x barlows:-

1524 (GMT+8):-


1525 (GMT+8):-


1526 (GMT+8):-


Seeing 2/10, transparency 5/10.

20101229 Sun

Relatively inactive, AR1138 is forming, still weak even in H-alpha. That prominence cluster is still strong.

1449 (GMT+8), with reducer:-


With 2x Tele Vue Barlows:-

1508 (GMT+8):-


1511 (GMT+8):-


1513 (GMT+8):-

Goodbye all my C mount lenses

I've owned several C mount lenses from 2.3mm to 150mm focal length. They're very great quality at moderate price, and they're compact and small.

I've tried to use them for some quick and simple DSO imaging by stacking with my DMK/DBK. The results are satisfactory for me.

However, since either DMK/DBK or my existing Lumenera requires a notebook to operate, this renders much of its portability advantage to null. I have been thinking whether they could be used for guiding or not, but with my 150mm f/3.2 sold, the rest were not just up to the task.

I've switched entirely to DSLR and Canon lenses, I'll stay at short focal length work, I won't bother to use a telescope and guiding is also not required.

Today, I have sold my last two of my C mount collections. You know, with the rapid growth of the micro 4/3 market, the price of my C mount collection grew! Not bad, right?

20101228 Sun

Seeing 4/10, transparency 7/10.

1508 (GMT+8):-


1509 (GMT+8):-


1520 (GMT+8), with 5x Powermate:-


That prominence is very interesting, it's bright enough. I've tried to use 1/60s with high gain, 1/30s with medium gain and finally 1/15s with low gain. Eventually I've used the one at 1/15s with low gain.

20101224: Silent sun on the silent day

Merry Christmas. Silent "day" reveals a silent sun, there's little activities.

1503 (GMT+8):-


This setup has been serving me quite well, but I'm thinking whether I should sell it or not.

The deal includes my Solarmax 40/BF10, the adapters for my Ranger, including the NGF-CM plus the tube ring. You can upgrade your Ranger to 2" focuser with motor, and you can do solar observation and imaging immediately. Let me know if you're interested.

20101223 Sun

Again, nothing special, seeing 3/10, transparency 5/10.

1440 (GMT+8):-


I had a brief look with a 20mm eyepiece, the filament extends in a very subtle way and it seems that it's connected to a dim prominence.

20101222 Sun

Seeing rather bad at 3/10, transparency 4/10, little solar activities.

1242 (GMT+8):-

20101218 Sun

The sky is still very clear, a little bit less transparent than yesterday but it's close. Seeing is better, however. I would rate seeing at 4/10, transparency at 7-8/10.

There's some nice prominences around. I've tried to do a big mosaic which is the first time with my Lumenera. Clear sky is a must for good mosaic or else cloud will be a huge hindrance. Good solar activity is helpful so that you have alignment point for registax in each individual frames. I found that the high frame rate of my LU070M is very useful, since it shortens the time required for each individual shot!

1153 (GMT+8):-


1156 (GMT+8):-


1206 (GMT+8):-


The mosaic is not posted due to the limitation of inline image of blogger.

20101217 Sun

It's very cold these days in Hong Kong (of course, using Hong Kong's standard), cold wind blowing and that's the reason why the temperature keeps dropping. It translates to poor seeing. The dusty sky is cleared as a side effect.

Seeing 2/10, transparency 8/10.




1127 (GMT+8).

I pulled out my Widescan 20mm to have a look, very interesting but not as active as the last time. Prominences here and there, but yet small. That filament is very nice and dark.

20101206 Sun

The sun is putting on a fine show today, we have a long filament, two big active regions, some very big (a bit dim) prominences.

I also had some visual observation with my Nagler 13mm, AR1131 is three dimensional! That large group of prominence is fantastic! You know, I can see layers of hydrogen in AR1131... you know, H-alpha solar observation is definitely addicting.

1142 (GMT+8), with reducer:-


1143 (GMT+8), with reducer:-


1145 (GMT+8), with 2x barlows, AR1131:-


1146 (GMT+8), with 2x barlows:-


1147 (GMT+8), with 2x barlows, not much more detail can be seen with a dedicated exposure, the Lumenera has a really nice dynamic range:-


1149 (GMT+8), with 2x barlows, AR1131 and AR1133:-

20101129 Sun

It's just not suitable to do any imaging today, cloud moving around with exceptionally low transparency. I've to use 1/60s for the exposure even during the absence of cloud. Seeing and transparency were both low.

Just a record.



taken at 1509 (GMT+8).

20101127 Sun

My wife is using the computer so that I've to use my netbook for the capturing. This time, I ran everything from DC, even the mount and the netbook. The Asus Eee can sustain around 50 fps I would guess. Not bad afterall, and things went on smoothly.

Seeing 3/10, transparency 7/10.

1254 (GMT+8):-


I also had a look through my Nagler 13mm, very nice filaments can be seen.

Celestron C5

After selling my C5, I have been staying with a 4" refractor but it's too long for indoor purpose. Yes, the quality is better but the usability is lower.

I sold that 4" refractor eventually, and now I'm trying to do some planet observation and imaging again with my Ranger (my only telescope at the moment), and I soon feel the limitation.

Now without a heavier mount but only my iOptron Cube and my Takahashi TG-SP II, I can only opt for something like a C5 again. It's just unique in its class. By going to a C6, you are way heavier, approaching to the weight of a C8! Thus, there's little reason to go for a C6 except for its price. By going a step backward to a 4" Maksutov, again, it could still be heavier than a C5!

Guess what, I might go back for a C5 eventually. Again, Borg 101ED is another choice, could be better too! Of course, I could go a step further by upgrading my Cube to a higher model, but that would be too complicated for me right now.

20101122 Sun

Very low transparency today, there's no cloud but the sky is white. Seeing quite good, but it's hard to evaluate since you cannot go high power due to the low transparency.

Again, taken with my Ranger which is now my only telescope on hand. Tracked by iOptron Cube, and captured with my LU070M.

1405 (GMT+8):


Tested the parfocality of my LU070M, and the Widescan Type III is no longer an exact match, but it's still the closest among all of my eyepieces. Might sell it eventually as a result.

20101119 Jupiter

Now I only have my Ranger with me. Jupiter was hanging outside, so I pulled out my Ranger to place it on my iOptron Cube for a quick look. Since my setup was well aligned to south and parked carefully after each solar observation session, a quick GOTO to the Jupiter was very accurate, the bright dot could be seen with my 20mm Widescan already. I moved it to the dead center and had it sync'ed.

Pushing it with a 2x barlows is easy, and then I soon decided to use my 5x Powermate! Then I moved again and sync'ed the mount again.

I first pulled out my Lumenera LU070M to get a short clip. I adjusted the frame rate to 15 fps in order to use exposure at 1/15s and by adjusting the gain, I get correct exposure without problem. The Jupiter disc was pretty clean on the screen, great and low noise performance. After capturing the clip, I moved back to visual observation.

Observing with a 5x Powermate + 20mm Widescan yields 120x, the Jupiter disc is nice despite pretty poor seeing tonight. Chromatic abberation is definitely there; by replacing the Widescan with a 13mm Nagler Type 6, magification goes up to 185x but the chromatic abberation is much reduced! To my surprise, the iOptron cube tracks pretty well, Jupiter stays in the dead center after five minutes and require only minimal adjustment after 10 minutes.

I enjoy the visual observation time, frankly, I was pretty exploited by the view of bigger telescopes, but I never feel bad only because there're some photons from the celestial objects hitting my eye :-)

Registax finished and here's the result:



2400mm effective focal length, and 1.5x resized after stacking.

a nice short and comfort observation session at home! I've to move back to my revision on Greek :-)

Before selling my DBK, I was thinking that I could always use my DSLR in video mode to capture color planet, but then I found it pretty troublesome. DSLR is much heavier and have a much different focus plane than a webcam or industrial camera, so setting it up would be more time consuming and it could even mean re-balance which is not easy for a small setup!

20101115 Sun

Foggy and cloudy... poor seeing and transparency.

1504 (GMT+8):-


Just captured a short clip during the best transparency.

I've tried to use my 5x, waited for so long without proper chance, so gave up.

Inventory Checking

Small adapters were not checked.

Telescopes/Objectives:

1. 70mm f=500mm achromatic objective mounted with 77mm thread
2. Tele Vue Ranger
3. Canon 10x30 IS
4. Fujinon C mount 75mm f1.8, Computar 6mm f1.2

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. 0.5x binoviewer corrector
7. Tele Vue 1.25" mirror diagonal
8. Chinese 2" mirror diagonal

Mount/Tripod:

1. Gitzo G106
2. Manfrotto 410
3. iOptron SmartStar GPS
4. Takahashi TG-SP II

Camera and accessories:

1. Lumenera LU070M
2. JMI NGF-CM with Tele Vue Ranger adapter
3. Solarmax 40 with BF10
4. Thousands Oak Type II+ for Ranger

--

As one can expect, with this combination, it's natural to look for something bigger... The bottleneck is on the mount, so what's the bigger aperture that I can get with my current mounts? C5 would be marginal, a Borg 101ED might be lighter but longer... maybe a 90mm Maksutov?

On the other hand, maybe it's wise to switch the NGF-CM to something with longer focus travel?

Right now my setup is obviously optimized for solar observation and wide field imaging, visual observation is pretty limited due to the small aperture, similarly planet imaging is limited as well. An upgrade to moderate aperture like 5" would be a nice step but then it might push the mount a little bit.

--

What I love to do?

Over all these years, I guess that I know what I really love to do and what I can really do. First of all, when imaging is concerned, I will love to do solar/lunar/planetary and also short exposure (several minutes) wide field portable imaging. Secondly, when visual observation is concerned, I love wide field scanning for brighter deep sky objects.

Orion 100ED + Unistar Lighter SOLD

Just passed it to a local folks who was primarily a photographer but he wanted to get into astronomy as well. A very nice guy and the transaction is very smooth.

Wish that he will enjoy this nice telescope, and better yet, enjoy astronomy as a very nice hobby!

--

Now, I've enough room inside my equipment cabinet. I can even put my TG-SP II inside, and when I've time, I shall also clean it up and re-organize everything inside.

I'm thinking to see what else can be sold. Like those small adapters, a 70mm objective which is now also used as macro filter, FCUSB, dovetail saddle, various filters....

20101101 Sun

Seeing very poor today, I won't even rate it... transparency at 5/10.

1501 (GMT+8), with reducer:


All the rest with 2x barlows:

1504 (GMT+8):-


1505 (GMT+8):-


1506 (GMT+8):-