Ken Self replied to the topic 'Align module - off target' in the forum. 3 years ago

universalmaster wrote: This seems counter intuitive to me. If the last allignment/plate solve was too a certain target, then this should still be the target after some imaging. I don't see a benefit of the target "driftigt" due to guiding and dithering, but maybe I'm missing something?
Is it possible to put allignments into the scheduler to circumvent drifting too far? For example realign every hour or so....

It seems that you and the OP have differential flexure so that the guide scope is driftng away from the imaging scope. Since its the guide scope determing the pointing during guiding it is moving the imaging scope off target - that is, the coordinates of the mount are now different. No different to slewing (slowly) to a target that is close by the one you started on. So the alignment module is going to align you to where the mount coordinates are now since that is what it understands to be the target.
Using the last target coordinates is not a good idea. You could have slewed intentionally to a completely different target.
The real solution is to fix the differential flexure.
A temporary solution is to repoint the mount to the original coordinates before aligning or, better still, load and slew to the first image taken.

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