Eyepiece projection factor - Baader Hyperion EyepiPosted By Gerry Doyle |
Hi there - I want to use a Baader Hyperion eyepiece for planetary imaging with a webcam, using the Baader T2 system to mount the webcam on extension tubes. I'm happy enough with the math for working out what projection factor I would get, if only I could work out the projection distance - which I'm guessing needs to be measured from the eyepiece field stop. Does anyone know if my guess is correct, and if so, where the field stop is with respect to the top element of the eyepiece? If I already had the eyepiece, I could work it all out by imaging a target of known size and working back from there, but I haven't bought the eyepiece yet and want to choose a fl that will give me a practical range of projection factors. Thanks
Gerry
Gerry