Quote:
Originally Posted by Peter Ward
I have a Chinese unit that couples to my FSQ...but for reasons beyond understanding couples to the coarse focus shaft.  |
My understanding is that the chinese steppers usually use a stepper that has a reduction gearbox, which give an inordinate number of steps per revolution, when coupled with the focuser, you end up with near sub-micron resolution per step in the focus mechanism. if you're dealing with large critical focus zones, the 10:1 reduction of the fine focus isn't necessary.