I also use a RigelSys Nstep on all three of my telescopes with step size on the SV102mm of 60. I would guess it takes about 1-2 seconds for the initial travel. I never noticed an issue with that but it is possible that SGP is not waiting long enough before starting the exposure. Could be that might be why sometimes the first point is off kilter with the rest. Not having the backlash set correctly will also cause this. Next time I am at the obs I will check this out.
I have a question for you about the focuser. I have a lot of trouble with my RigelSys focusers giving me serial errors and not connecting without a couple of cycles of:
- closing the current RigelSys connection dialog that gave me the failure
- checking the Task Manager to make sure the RigelSys program is not still running in the background processes. If it is terminate it there.
- powering down the USB hub
- powering the USB hub back up
- running the RigelSys program again
- checking the Connect box to connect to the RigelSys hardware. At this point the odds are 50/50 that it will fail again so this cycle usually takes one or two iterations to get successfully connected.
Very annoying. Have you ever seen this and if so how often?
I have spent a lot of time with the RigelSys people trying to resolve this to no avail. There may be a serious problem with the serial connection code here.
About your 1 second exposure problem, I am about out of ideas here. The symptoms are exactly what I have with my 6D if I don’t have those mirror settings set to OFF and 0. You might try ON and 1 second. If that does not fix it then send your logs to Ken. Once you get the exposure time fixed, I don’t think the travel time will matter that much, assuming the exposure starts too soon since you will be taking longer exposures and it will only affect the first one significantly anyway.