Re: confusion over settings for stepper motors


I am not sure how big this is or the OTA he has on this, and i don't know much about telescopes in general  because i am just implimenting Onstep fror a friend so this may not be relavent. My friend has an EQ5 mount and there have been a lot of conversions of this and they most seem to all have basically a nema 17, 200 steper with a 3:1 ( or so) reduction and then the worm which i think is 144 teeth. so the implication is that motor plus microstepping plus about 420:1  reduction will work.
Given suitable motor, is a direct drive ( or 1:1 belt)  to the 359 tooth worm  feasable or desireable?
is it possible  to remove the intermediate 20:1 worm box or is it integral with the scope mount and engineering wise just not feasable?
if you leave the 20:1 gearbox in what is the minimum goto speed that is acceptable? i.e if you are going for all night run on a particular point, is it a problem to do a goto lasting 30 minutes, even posibly before it gets dark, or are you wanting to goto a lot of different points  in quick order , for instance as a group demonstration at a star party?

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