Now the days are getting shorter in the northern hemisphere, it's time for me to work on my winter photography plans. Specifically going astro! I've been interested since I was little, but rarely put it into practice with observing by anything other than naked eye. And my few attempts with normal camera lenses have been interesting but I do want to move up a level.
Telescope wise, I have no idea what I need/want. I do want a motorised equatorial mount. Computerised auto-alignment would be a big plus. I have read through other previous posts here but I think I still need some pointers.
Subjects - whatever I can see I guess. For starters, the moon in detail and planets. At least surface detail on Jupiter, resolving GRS would be really nice.
I do live in a city so light pollution is a bit of a problem. I don't know how far out I need to go to get much clearer skies. Weather allowing of course. I wonder if a low pressure sodium lighting filter helps much? Only found one so far, almost wondering if they really exist...
Focal length/magnification/etc - no idea. With a 300mm camera lens, Jupiter's disc is only a tiny handful of pixels wide currently. So I'm guessing "as much as possible" might not be too bad? Providing it's usable, I'm guessing something around 3000mm will be fine.
T-mount... here I'm a little confused. I have what's sold as a T-mount adapter. One side fits on camera. One side has another screw thread for whatever else. It is my understanding that on here you screw the appropriate adapter for the telescope eyepiece. However, in Gordon's video, it's shown as a single item. I can imagine the two parts being made as one, but what is the correct terminology for the mount? I've also heard it called T2-mount. Ooh, reading some more, I now also see it called T-ring. edit:
suddenly it becomes clearer. I got the ring, just need the other bit to join to scope.
Further to that, on a quick search I see you can either put the camera at the prime focus of the scope directly, or leave the eyepiece in place, with or without lens. What is the “short version” impact of leaving the eyepiece in? I assume it gives effectively a focal length increase at the cost of light? Likewise digiscoping?
My budget is open. I don't want to go crazy, but at the same time I do want something that will not leave me looking to replace sooner than later. Over £500 for the system is not a problem, but the further up you go, I'll need more convincing that it's worth it.
For an example of something that looks interesting, how about the
Celestron C8-NGT? Seems to go for around £650 in the UK. 8 inch (203mm) aperture, 1000mm focal length, f/4.9. My initial feeling is the focal length is a bit short so if I got this, I will need to use some techniques to effectively extend it. Their spec does claim a photographic resolution of 400 lines/mm, but I don't know how that compares to typical DSLR sensor resolution and therefore estimate the useful focal length that could be extracted.
Random thought. The use will be mainly for astrophotography... but at 1000mm, I'm wondering will it double as a rather bulky daytime telephoto too? Obviously at 30kg I'm not gonna hand hold it
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It's hard to get a lot of info into a short amount of writing. Next time I'll have to post one question to start with, and drip feed the rest once you've bitten 
