Hi Steve, and Welcome to the group,
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I don't really feel qualified to answer your questions directly, but I'm sure there are many in the group who can. However, I would suggest getting along to a viewing night and having a look at what equipment, OTA and mount, various people have for their particular interest. You also have to clearly identify your own specification requirements as to whether it is lunar or DSO photography that is taking your interest. Make sure you identify that you will be using a Canon EOS 10D for the photography (my assumption from your signature block), as it will also have its peculiarities too. I'm still trying to get successful photographs with mine.
Research as much as possible, talk to people in the know, look at what people use, search the group and be sure of your goals before you commit , because astronomy and photography has a nice cash register ring to it
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Cheers,
Graeme