The CP990 mounted on the ETX90. With my eyepieces the CP990 just barely manages to
avoid vignetting. I can use all eyepieces with or without Barlow and get full
size 2048x1536 3.3MP images without vignetting and decent quality. The air must
be still for you to be able to get quality images! Also, you really need a good
tripod as well as a remote release shutter or self timer...
