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Hi Greg,
I think it is a mistake to expect that T-Point and PEMpro drift alignment are going to "agree" very much on where to place your PA! There has been endless and heated discussion about this on the SB forum. If I have digested the discussion properly T-Point is making a mathematical construct of all the pointing combined with flexure issues of every setup and offers various PA recommendations based on what one desires to do. But, PEMpro offers great PA at just one sky location. (Dec=0, etc) So, it seems all PA Is a compromise. Patrick W. has said (perhaps reluctantly) that using drift alignment is good enough as long as one also uses T-Point to model the sky so that Protrack can do its thing. But, so is T-Point PA!! Of course, if you moved the polar axis when you ran PEMpro drift you've got to recalibrate into your large model to get it to work again! The recommendation is to recalibrate as a "portable mount." The other possible reason your new T-Point model didn't work so well is that maybe your polar axis moves, especially MA, might have not been as accurate as you thought. There has been much discussion about that as well and now are methods to move using fiducial stars to confirm accurate adjustments. So, you re calibrated after you made moves of PA?
Peter
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