Quote:
Originally Posted by johnnyt123
I am still tossing up between the QSI683 or the QHY9.
there is a saving of $2500 if i purchase the QHY over the QSI with essentially the same filterwheel and filters and OAG setup albeit it isnt integrated with the QHY and the filters are a little further away from the CCD chip than the QSI. can the vignetting be overcome by using 50mm filters rather than 31mm filters if the filters are a little further away from the CCD Chip?
John
|
Your next consideration is then how much weight your focuser will manage, and how much back-focus is available. The larger filters will eliminate the vignetting at that point, but make sure your OAG pickup is in front of, and not behind (ccd side) the filters, particularly for NB.
Cheers,
Andrew