Quote:
Originally Posted by Joshua Bunn
By ''guide rate'' do you mean the aggressiveness of the guide corrections?
|
No. The guide rate is the speed of the
correction that is applied to the telescope's position expressed as a fraction of the sidereal rate. The default rate for SB mounts 0.5. I.e. on the RA axis this means that the tracking rate will change to either 0.5 or 1.5 times the sidereal rate depending on whether the tracking error is west or east. On the Dec axis corrections will be +-0.5 times the sidereal rate. Aggressiveness is the proportion of the computed correction that is applied. I.e. a 1 second computed correction will be only a 0.6 second actual correction if aggressiveness is set at 6 (10 = full correction applied) ..... I think!
.
Quote:
Originally Posted by gregbradley
If you are getting oscillating guide errors my suggestion is to make your balance slightly off to the east to load the gears a tad so the backlash doesn't cause a bing bang effect. That worked on my PMX when I encounter that which I have the last 2 times I used it.
Greg.
|
Tried that with no effect. There is no backlash per se. My theory is that this is more a vibration set up when starting and then stopping (via a guide correction) a large mass. The measures I've taken support this theory - adjusting the spring plungers (small effect), reducing aggressiveness and increasing guide period. I suspect now, if I'm right, that correct guide rate + aggressiveness settings will solve the problem. However, I won't do any more testing until I've got my collimation sorted out.