Thursday, May 29, 2008

Total Solar Eclipse Setup: Integration testing

Finally got time to put everything together.

The TG-SP II can take my Borg 45ED II with my Canon 450D + Kenko 2x + Canon 200mm f2.8L without problem and what's so impressive is that, I don't even need to use more than the bundled counter weight!

But anyway, I will bring one more counter weight in case needed. Since I still didn't put the DMK and the Solarmax filters in place, but they're pretty light.

The Canon is front heavy with the 200mm, so the counter weight requirement is different for different side of the meridian. So, I guess I will buy a mounting ring for the Canon 200mm f2.8L to make the setup in better balance.

Okay, time for picture, note the position of the counter weight.

With the kit lens, everything is in good shape, since the whole thing is so light, there's no problem.

With the 200mm, the camera becomes front heavy, different counter weight is required for different side of the meridian.

With the 2x teleconvertor, the camera becomes even more front heavy. A mounting ring is going to solve the problem, and the mounting ring will also allow me to adjust the orientation of the camera so that I can frame the target field in a more flexible way.

A Intes dovetail bar is used for mounting both the camera and the Borg at the same time. The Borg will be used with H-alpha filter system (Coronado Solarmax 40 + BF10), and the Canon 200mm with 2x will be used with white light filter. During the eclipse, I might put a Konica Minolta Z5 there to take video as well.

Finally, the same setup will be used at night for simple wide field shots, but in that case, I will only use the kit lens and the Canon 200mm f2.8L at prime focus without the Kenko 2x. The Borg will be used with a Meade 9mm illuminated reticle eyepiece for guiding purpose.

Canon EOS Utility

I found that the EOS Solution CD will not install EOS utility in my desktop PC. I browse around the CD and I found that EOS Utility is actually there, but the installation software just does not show it up in the list of options.

Then, I checked the same CD from another machine, and then some more softwares show up including the EOS utility. I guess it's due to the difference in versions.

As the manual suggested, I guess it needs SP2. Local Canon technical support suggested me to install CDROM:\SOFTWARE\DOTNET\COMMON before the installation takes place, but it still won't work. However, it does work correctly on Windows XP SP2.

Anyway, since my notebook does have SP2 installed. I found that the camera will not work with USB1, originally I think it will just be slower, but I was wrong, it won't even work.

After the installation, I immediately tried out the software. Yes, it's fantastic! It even works with Live View! The delay is very acceptable, and with the bigger screen of my notebook, focusing is even easier! Also, it comes with interval shoting function, also you can use BULB mode as well. That's a great news to astrophotographers! Finally, the images can be downloaded directly into the notebook, that saves the need of a big SD card!

So in summary, I won't need to buy a timer remote, I won't need to buy several SD cards. But instead, I will be buying a small USB powered hard drive.

Wednesday, May 28, 2008

Shopping List for the Solar Eclipse Trip

[Updated on 15th of July, 5th of July, 2nd of July, 19th of June, 17th of June, 16th of June, 13th of June, 6th of June, 5th of June, 3rd of June, 2nd of June, 30th of May]

Since I think that I will be spending less time on the equipments, I can cut a few more items, for detail:-


1. Backpack for 450D, kit, 200mm f2.8L, my Borg 45ED II, Solarmax 40/BF10, a small eyepiece box, tripod and TG-SP II, also my Konica Minolta Z5 DC. Should be usable for daily purpose during the trip, like to keep a bottle of water, some handy stuff, etc.

Target on Lowepro CompuTrekker Plus AW:-,1925.htm

Airline portable, around $1200. Seems this one is not too good for daily purpose, but...

--> Now, I want a smaller version to maximize the chance for daily usage, especially during the trip.


No item pending.

On hand:-

2. 8G Class 6 SDHC card, around $300 budget

Finally I bought a 8G Verbatim SDHC, the writing speed is less than class 6 despite it claims to be class 6, for reading, yes, it can. Anyway, I'm not very much a fast shooter, like to shoot flying birds.

3. Backup battery for 450D

Third party battery (1280mmAh) ordered from ebay on 2nd of June, $9.18 USD shipped, received on 6th of June.

It looks very nice, even with a very familiar looking battery cover, charging time is similar compared to the original one, and this one is lighter, I guess it has lesser actual capacity, therefore.

I've used this battery for one charging and discharging cycle, it's of very similar capacity with the original one, not bad indeed.

4. Mounting ring for the 200mm f2.8L

--> Ordered from ebay on 3rd of June, $23.98 (USD) shipped on 4th of June (expect 7-14 working days), arrived on 19th of June, pretty slow. The item is not well packed, and its outlook is different from the photograph shown! What I mean is, the design is just different. I got a $5 (USD) partial refund for that, and I tested the ring and it solved the balance issue nicely.

6. Adapter for EOS -> 2" (ScopeStuff), and 1.25" -> T and T ring for EOS, also a longer dovetail plate (8.5")

--> Ordered online on 31st of May, $1152.7 HKD shipped on 3rd of June, should be arrived by 16th of June, but I've no time to fetch it yet; I fetched them on 17th of June, all items very nicely made, I'll write another blog entry for them.

No Need:-

5. Chinese timer remote for 450D (No need now, since EOS utility did it so well!)

7. A USB powered external hard drive, the bigger the better, at least 120G, around $700 budget (no need so much storage now)

8. A Canon 50mm f/1.8

I bought one eventually, but it's not for this trip.

Saturday, May 24, 2008

20080524 Sun

The sky is pretty good, I would say the transparency is 7/10, maybe due to the short shower this morning. Seeing is like 4/10, not bad. Not much solar activity today, only a couple of small prominence (dim, too), as well as short filament, and a very weak active region, maybe the remnant of one of the active regions found a couple of days ago.

Telescope: Borg 45ED II
Filter: Coronado Solarmax 40 with BF10
Camera: DMK 31AF03

1349 (GMT+8):-

1350 (GMT+8):-

Finally, a white light shot taken with my new Canon 450D, with Kenko 2x teleplus and Canon 200mm f/2.8L wide open, the first only is cropped only, and the second one is further processed. Thousand Oaks Type 2+ Glass filter is used.

This shot is a test shot, this combination will be used in my total solar eclipse trip. The solar disc size seems okay, not too small especially with a compact setup like this. And then for image quality, I shall try again when there're sunspots on the disc.

Cropped only:-

Further processed:-

Canon 200mm f2.8L

The Canon 200mm f2.8L is very nice! It focuses very quickly, and silently.

I placed it side by side with my Borg 45ED II (with JMI NGF-S), and the Canon is smaller!

And I also placed it side by side with my Tele Vue Ranger, the Canon is bigger in aperture but it's smaller in size!

As I checked before the purchase, this lens should be able to use wide open for star field imaging, so what else can we ask for? It can also be used for daily usage.

Even with the Kenko 2x Teleplus, it's still smaller than both of the Borg and the Tele Vue. This will be my choice for the solar eclipse and I shall try out this combination on the sun with a white light filter, as well as on the moon to test its performance.

Friday, May 23, 2008

My First DSLR

I have purchased my first DSLR yesterday, it's a Canon 450D.

Why I've chosen a 450D is that, I want Live View but I don't want to weight of a 40D. The new better quality kit lens is also one of the motivations. That effectively saved the money for a wide field lens as well as a daily usage lens.

Together with the 450D, I also bought a Canon 200mm f/2.8L. This is one of the most "economical" L prime lens which performs good even on stars. It is fast, and it's also light weight. That makes it suitable for my Takahashi TG-SP II, to form a very portable wide field setup. I believe that I won't become serious on deep sky imaging, so this lens is the entry level ticket for me, as well as to let me do "something" even in non-astronomy oriented trip. This lens is paid by my wife, she insisted to pay for me. Somehow it's hard to have a wife to go shopping for this kind of things with you, and it's even harder to have a wife who will even pay for you. :-)

I am going to buy adapters for my Borg 45ED II as well.


On the next day, I also bought a screen protector and a Kenko 2x. Enough for this moment. After several months maybe I will also buy a 50mm f/1.8 (or f/1.4?) as well as a wide angle, or even fisheye lens.

Wednesday, May 21, 2008

Double Pass: a failed design?

Just received this:

Sounds like the double pass design is not working very nicely, even the manufacturer gave it up and got back to double stacking.

What makes Lunt so interesting is that, they're going to produce something new, innovative and also set a new price point! However, now without double pass, their offering is like gradual improvement over the old company.

Yes, we have so many nice improvements here and therefore, and we also have a better price point, most probably. But then, it sounds like that we will be getting similar product at the very core.

What's changed over the similar offering:

1. A bigger objective
2. A singlet vs a doublet (not exactly a good thing?)
3. Narrower bandwidth promise
4. Less sweet spot promise
5. A better focuser
6. No more built-in solar finder (a bad thing)

Not as attractive as before, obviously. The good thing is that, they're going to keep the same price at first, despite they're going to double stacking. But that would be changed very soon.

About the Upcoming Total Solar Eclipse (Chinese)

我將會跟隨香港天文學會,前往伊吾觀測在 2008 年 8 月 1 日的日全食。

日全食是由於月球剛好擋著了太陽的光線,但由於月球的影子並不太大,所以能夠觀測到日全食現像的地區範圍不會太大,所以有人說觀測日全食的人為 "shadow chaser",即是追著月球影子的人。因此,日全食其實就是天文愛好者與月球影子的相會。




Tuesday, May 20, 2008

2008 Sichuan earthquake

It's a very terrible one. Other than personal donation and prayers, it's hard to do anything else.

Until late last week, Hong Kong Astronomical Society launched a sale on some books, planisphere, etc. All the money collected (without deducting cost) will be donated. So, I bought some as well, to take the chance to express our support as amateur astronomers. We share the same planet Earth and we're under the same sky.

I've also delayed (or even canceled) the purchase of some equipments to spare the money for personal donation. I understand that these limited effort has very limited effect, but it's just to show my care and concern.

Let's do something.

Sunday, May 18, 2008

20080518 Sun

Similar atmospheric condition as of yesterday, slightly better in terms of transparency, since I can use slightly faster shutter, however, we have thin cloud moving around. So, I would say the condition is actually slightly worse. Anyway, just a record. The three active regions are still there basically, but they're getting more subtle.

Telescope: Borg 45ED II
Filter: Solarmax 40/BF10
Camera: DMK 31AF03

1457 (GMT+8):-

1458 (GMT+8):-

Saturday, May 17, 2008

20080517 Sun

It's essentially cloudy, transparency is like 1/10, the sky is all white, and we have a very dim deep orange color sunshine. Seeing is like 4/10, actually, quite hard to evaluate. There's not much prominences detectable. Several small active regions (AR994, 995 and 996) can be seen despite the very poor transparency which washed out most detail.

Telescope: Borg 45ED II
Filter: Solarmax 40/BF10
Camera: DMK 31AF03

1352 (GMT+8), surface detail with prominences pushed:-

1353 (GMT+8), prominences centric exposure:-

1355 (GMT+8), again surface detail centric exposure, alternative color scheme:-

Tuesday, May 13, 2008

20080513 Moon

It has been quite a while since the last observation/imaging session, the sky was either cloudy or I was occupied. Anyway, got a short break today. Seeing was pretty poor at 3/10, transparency also low at like 4/10.

Telescope: Tele Vue Ranger
Camera: DMK 31AF03

Wide field at prime focus:-

2242 (GMT+8):-

Close up with Tele Vue 2x barlows:-

2247 (GMT+8):-

2249 (GMT+8):-

2258 (GMT+8):-

Saturday, May 03, 2008

20080503 Sun (Cloudy)

It has been cloudy for so long. Today, we got some gaps in between the cloud, but it's just too bad to capture any surface detail, but prominences are possible by overexposing everything. I've to keep sliding the exposure/gain manually in response to the thickness of the cloud in real time!!!

Telescope: Borg 45ED II
Filter: Coronado Solarmax 40 with BF10
Camera: DMK 31AF03

20080503 1403 (GMT+8):-

Another video composed of two video clips which were killed completely by cloud, but then we can still see some surface detail during some moments:-

Friday, May 02, 2008

Canon 450D and Total Solar Eclipse

I finally sit down and do some calculation, to my surprise, the size of the solar disc will be only around 750x750 pixels at 400mm focal length!

Therefore, even if I get a 2x tele-extender to use with a 200mm f/2.8 (i.e. 400mm f/5.6), the size will be just similar to my DMK + Borg 45ED II combination.

When I asked in a local forum, a shadow chaser told me that we will only need 4-5s of exposure at ISO 100 even at f/11 to capture the fainest part of the corona. Therefore, if I use ISO 800 which is still rather clean with today's technology, the exposure is well manageable even at f/14.4 of my Borg 45ED II with 2x barlows! That will be 650mm which is quite pleasing. With such short exposure, even a roughly polar aligned mount will do the job.

So it seems like that a 200mm f/2.8 is not really necessary for this trip at all.