OK, got it.
BTW, did my first APPM mapping run last night and activated tracking rate correction for the first time with the Mach2. (Third use of the mount under the stars. ) Got a series of 56 x 4 min. unguided narrowband exposures over 3.7 hours. The modeling - 68 points or so - took a half an hour while it was getting dark, the sky was settling down and the optics were cooling down.
It worked wonderfully. Used all 56 frames in the integration stack.
I am very impressed with the mount and the software.
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