I am very new to Astronomy but have been heavily into photography for more than 50 years.
I currently have many Nikon lenses one which is a 600mm AFS ED F4 lens which I would like to mount onto a dovetail plate to use on my HEQ5 mount and experiment with imaging with my Nikon D810 and Nikon D500.
Has anyone tried lenses of this focal length on an equatorial mount.
I have used an 85mm and 135mm lens but there is a guy over on Cloudy Nights that has been using a Canon 600mm f/4 on a EQ6 for a number of years with a lot of success.
My point is, it is definitely possible and it does get done