I have been looking at Alt/Az tracking over the last week or so. Unlike an equatorial mount, objects viewed through a scope on an Alt/Az mount will have different rates based on their position in the sky in relation to the celestial pole as they rotate on a circular path around it.
I have a SKywatcher AZ3 mount with slow motion screws and am just looking at tracking something for a maximum of 15-30 min, ie find it turn on tracking ..... show the wife and kids
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The best I have been able to figure out at the moment is to have a look at a star chart program like Stellarium, work out the change in Alt/Az over an hour and set the rate on my drive circuit to match. I am currently looking at using a stepper with a 1350:1 reduction drive attached to it and a basic drive circuit to get things moving.
I haven't even looked at what sort of errors I could tolerate with 40-60x magnification on my 80mm refractor, but I guess field of view for the given eyepiece will be a key ingredient.
cheers
Damien