Scanning for focus when original offset is close to zero
seichhorn opened this issue · comments
I'm finding that when I lock my focus lock with an offset very close to zero, if I lose focus and enter the scan_focus routine I end up erroneously accepting the first measurement. This seems to be because 1) the uc480camera is returning total_good = 0, and 2) the difference between my IR spots returns as 0 owing to no good fits. The difference of 0 passes the threshold for the difference relative to the offset in the handleQPDUpdate step of the ScanMixIn class. Is there a better value to return here instead of 0?
Do you have this problem with the current version? I encountered what I think may be the same problem, and we pushed a fix recently.
Thanks, I was on another branch and missed that commit, but it seems to have fixed my issue.
I'm still puzzled why the "sum" check is not catching this. When there are no spots on the camera the "sum" signal should be below "minimum_sum". Does no one set "minimum_sum" properly? Or does this just not work for some other reason?
My focus lock sum that is only ~2-fold lower when my spots are badly out of focus/undetected, and couldn't find a way to set it that guaranteed I didn't erroneously pass the minimum_sum threshold during the scan despite being out of focus.
Okay, thanks.