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Sidereal rate will result in a star that barely moves, because obviously the
mount's trying to keep the star stationary; you need to use the mount's slowest slewing[or guiding] speed,[ if it is motorised] or control manually, so that the star takes at least a minute to cross the screen from right to left, then reverse direction, and another minute back to the starting point.
When doing the first couple of iterations you can reverse direction after about 30 seconds, as the inaccuracy will be obvious. You will need longer runs for the inaccuracy to show up as the alignment gets close to your aim.
This sounds a pain in the a--, but after a few times it becomes easy.
You can change your accuracy requirements according to the focal length
of your imaging optics. If you mark the ground in some way, so that you can plonk your mount down pretty much in the same spot each time you use it
you can considerably reduce the time it takes to do DARV. It will probably
take 45 mins or more the first time, as you get the hang of it, and come to see how much you need to move an axis to correct x amount of inaccuracy, but after a few setups you should get down to 15-20 mins.
cheers raymo
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