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by jcims 1613 days ago
Your site got hugged to saturation but this is something I've been wanting to do for a while. I just got a sort-of ridiculous telescope (Celestron 11" SCT on alt/az mount, 2800mm focal length) and have been tinkering with ADSB for years. Can't wait to check out your work!
1 comments

That would be awesome! How fast can those mounts move? Would they be able to follow an aircraft? I have found that more zoom actually makes things a little tricker because you have to make sure it is leveled and aligned precisely. When my camera is fully zoomed, it has about 1 degree vertical field of view.
I've got a 6" Celestron, and I think it would be capable of following a plane that's sufficiently high up. It can slew a max of 5°/sec, so that would be ~500mph at 10000' or well over 1500mph at 30000'.

Because it's a telescope, it's designed to be aligned at night. It's more of a pain to do during the day (such as for an eclipse or I guess tracking planes). But there's no reason you couldn't align it to stars at night and it will its alignment pretty precisely. I'm not sure how much drift there is in that over say 24+ hours though. It's also smart enough with the Celestron controller to never point at the sun even during a slew. I'm not sure if it has that same safety feature when controlled from a computer, which would be a major concern with daytime use.

But a 6" f/10 (so ~1500mm lens) telescope with a full frame camera is still a 1° field of view so the same as you have now. Smaller sensor would be tighter field of view.

And of course the obvious drawback: None of this setup would be weatherproof

That is interesting! There is this cool piece of software that looked like it helped with a lot of this. It did visual object tracking with telescopes... but it is no longer available: http://www.optictracker.com/What_is_it.html

Alignment has been a big pain for me. I might actually have to look at how to use stars to correctly position everything.