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NightHawk · Joined: 05 Dec 2006 Posts: 35 Location: DB

Quite a cloudy night this evening, but it turned out ok. On a 25mm. I couldn't get the camera very close to the lense with the fear of scratching it.

On a 9mm. It was too bright. Like a flashlight on camera.

Hopefully I will be able to get better photos in the future. When the nights are darker, clearer and I have perfected the webcam settings.

Are these too small to use Registax?

I know it isn't the biggest telescope in the world, the Meade 60mm. But do you think I will get an ok picture of Saturn?

Thanks
Neil

bhenderson50 · Joined: 11 Dec 2006 Posts: 48 Location: dalgety bay

Hi Neil,
welcome to the fascinating world of astroimaging. I bet you were really excited to get your first images!
Couple of points about your post :-
1. if I understood your post correctly, you took the images with the webcam lens inplace. This is very difficult to do successfully. What you need to do is to unscrew the webcam lens, and replace it with an

adaptor [these can be bought from Astroengineering, via the Telescopehouse website] which will allow the webcam to be inserted into the 1.25" eyepiece holder of the telescope. What you are effectively

doing is to replace the short [around 10mm] focal length webcam lens with the much longer focal length telescope objective, giving higher magnification. The adaptor allows you to rigidly hold the webcam wrt

the objective, and to accurately focus the objective on the webcam ccd element. I can lend you an adaptor to try this out if you would like.
2. I am not sure if the images you posted are single webcam "photos". If so, what you should be doing is to take advantage of the very high speed frame rate capability of the webcam to acquire around 1000

frames [say 100s at 10fps] of video, then use Registax to select the best of those frames, align and stack them to give a nice bright single image. Of course, the length of time you can acquire video over

depends on how well aligned your telescope is! If you would like some help with this, feel free to call me or e-mail me.
3. yes you should be able to take images of Saturn, Jupiter, Mars etc. The moon is a great training ground!
Have a great time learning this new skill,
Bob
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bobh

Solar B · Joined: 07 Dec 2006 Posts: 100 Location: Dalgety Bay

NEIL
your top image is amazing for your first go and without the ease of the adaptor that bob has already discribed . brian

NightHawk · Joined: 05 Dec 2006 Posts: 35 Location: DB

pbholmes · Joined: 15 Nov 2006 Posts: 124 Location: Dalgety Bay

Nice pics Neil.

I too have been planning to have a go at webcam photography, but I haven't quite got there yet.

bhenderson50 · Joined: 11 Dec 2006 Posts: 48 Location: dalgety bay

Hi Neil,
I think the best thing to do would be to let me have a look at your webcam. You could either bring it to me at home, or if you prefer, bring it along to the next meeting at the Bay Inn. All of the webcams I have seen have a removeable lens, which would allow you to fit the adaptor I mentioned. Until I see your webcam, I can't recommend which adaptor would be suitable, but we could certainly try mine first.
Your video settings for the webcam are fine, although I would recommend running at 10fps max - this is because at high frame rates a compression algorithn comes in to play, which can lose you some of the fine detail. 10fps will overcome this limitation. When you say you view the video frame by frame, how are you doing this? If you are manually reviewing the frames you will take a long time to process even a shortish video session. Registax will automatically review the frames for you very quickly, governed by quality limits you set up at the start, then will align and stack the selected frames for you. It's a great piece of freeware!
Take the quoted x233 magnification with a huge dose of salt! The generally accepted limitation for any telescope is about 60x the size of the objective in inches [spot the American influence!], which for your 60mm telescope would give an absolute maximum of around x140. This would be for ideal viewing conditions, which will almost never happen. x50-60 is the mag range you will most often use, and probably around x100 is the highest mag you will be able to use.
What this actually means is that the object you are viewing is brought 100 times closer to you.
Finding Saturn, which is starting to become interesting in the eastern sky later in the evening, can take a bit of practice, but trust me it is worth the effort. Nothing quite beats the "wow" factor of your first live view of Saturn.
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bobh

bhenderson50 · Joined: 11 Dec 2006 Posts: 48 Location: dalgety bay

Hi Paul,
I would be happy to let you try out my webcam adaptor. You could either bring your webcam up to me at home, or bring it along to the next meeting. Whichever suits you best.
Bob
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bobh

pbholmes · Joined: 15 Nov 2006 Posts: 124 Location: Dalgety Bay

Hi Bob,

Thanks for letting me try out the adapter.
Would it be OK if I bring my OTA as well as the webcam, as I would like to see how they fit together.
Is it a prime focus or eyepiece projection arrangement? (Reading it back, this question makes it sound like I know more than I do. I've read up on it, but never actually tried it.)

I'll contact you by Private Message to arrange when.

Paul.

bhenderson50 · Joined: 11 Dec 2006 Posts: 48 Location: dalgety bay

Hi Paul,
the adaptor in question screws in to the front of the webcam, in place of the lens. The adaptor then allows you to insert the webcam in to the telescope 1.25" eyepiece holder, which allows the eyepiece focus adjustment to set the ccd element in the focal plane of the objective. Easy!!
cheers and Happy New year,
Bob
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bobh

NightHawk · Joined: 05 Dec 2006 Posts: 35 Location: DB