Hi all,
I would like to grind a mirror but not sure of the focal length I should be aiming for. I really enjoy gazing at the planets and the moon and have been told that I should aim for a longer focal length….but have not been given any specific advice. I would like the scope to be a dedicated planetary scope and was thinking in the order of f13-15. Or is this just ridiculous for a Dob? [I currently have a 8 inch (f10)]
I am aware that this will make the tube very long especially if I go for a larger mirror (thinking 12 inch). Does any one have any advice?
Thanks...
