Gday Fred
The Melbourne weather saps ones desire at times
But i do have the DEC done.
I can currently watch through my EP and do a smooth "controlled" manual move in Alt or Az of around 10 arcsec, using only 2 fingers.
Using the motor in DEC, its even smoother.
However, i am also using 1/2" UNEF threads on a lever arm of 280mm to do my moves.
When you look at the very short lever arms and coarse threads on most cheaper GEMs, the ability to do low power fine adjusts just isnt there.
Also, why I plan to use the drifting method, vs TPoint etc as
1) Its exceedingly cheap
2) I dont need encoders etc, and dont need to account for any lash in the adjusting mechanism. Just watch the star and move accordingly
3) I was thinking that if you used drifting, at any time during the night,
if you slew to a new locn, you could start a quicky drift test and if necessary, get the mount to micro adjust itself for that locn
This removes all the refraction, flexure etc effects,
and means no complicated models are reqd.
Just point and tweak.
Andrew