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Old 09-06-2011, 09:45 PM   #28
pylon
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Quote:
Originally Posted by sclitheroe View Post
The images were taken from a 25km orbit...what do you think your 8" could see at 25km? A car? Just curious, I have no idea what size optics this spacecraft has on it.
Good question. Honestly, I can't answer that exactly, I don't know the exact formulas to use. I do know, when I have set up at the dog park by in Britannia, where the dog walk is, I can see the golfers over at Earl Grey. I think that is 2.5 kms.

It would be a combination of eyepiece, barlow, total useful resolving power, F-rating...etc.

I was just using an example, as I was using a fencepost in the distance this weekend to calibrate the star finder on my scope with a 12mm eyepiece, and noticed the nail sticking out of the top of the post which I thought was neat. So we just walked to the post, and used a GPS app to measure the distance which was 1050 metres.

Edit: wow, just looked at the specs, that scope is f 3.59, which is awesome. That is fast, and explains why they can get such good images. My scope is F10, which is pretty normal with most amateur stuff. I have a focal reducer that takes it down to F6 I believe, but you give up a lot of magnification.

Last edited by pylon; 09-06-2011 at 09:49 PM.
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