Quote:
Originally Posted by LightningNZ
The biggest problem as I see it would be that you need to refocus for each colour. Given the focusing with a CCD or dSLR is annoyingly difficult anyway, spending lots of money on a heavy, computerised focuser that remembers which position it should be in for each colour and at what temperature is probably not worth it. Better to get an APO (or even better a mirror based scope) and not worry about focusing and filtering out chromatic aberration, then you have a great general purpose scope too. 
Cheers,
Cam |
Most threads I read have users refocus for each colours anyway to get best results even for parfocal filters, I thought if refocus anyway maybe achro would do as good.
So people use mono camera and achro for sun or moon should probably use APO instead for mono work?