I use ACP Scheduler to run a robotic variable star program with a 900 mount unguided. Tracking in particular with the longer exposures sometimes required is problematic and substantially impacts signal to noise levels I can achieve. At least some of this I related to mirror flop on my c11. I modified the instrument in an effort to mitigate this, but was never satisfied that I had eliminated it. I have now replaced the scope with a Meade 12" ACF, which allegedly eliminates or reduces mirror flop. In theory, APCC could greatly enhance my tracking and hence data quality. I am wondering if anyone here has had success in using APCC's modeling ability with an SCT and especially a Meade ACF without using mirror locking. -- James (Bruce) McMath
