I use an Optec Gemini Focusing-Rotator that has 0.11 micron focus steps. Using 2500 steps causes the V curve to span about HFR 5.2 to HFR 1.5. I have smart focus disabled since I use a 12" Meade f/8 LX850 OTA and smart focus has never seemed to provide any benefit. The focuser appears to have an accurate temperature readout. Sometimes I disable SGP's temperatrue compensation and just let the Optec do TC continuously in the background. The Meade OTA has a significant TC requirement.
I will repeat the auto focus routine for each filter and compare the results to the previous ones just to verify I'm in the ball park. I will also monitor the auto focus runs more closely to verify that the move to the filter position is performed after the auto focus using the Lum filter. I assume that will show up in the SGP logs.
Thanks for the info.
Charlie