MiG
28-03-2005, 01:12 AM
Is it possible to use a field reducer or some other sort of lens arrangement to get a low magnification on a large telescope while maintaining a 6 mm exit pupil?
Example: On my 250 mm Dob, a 30 mm EP gives 41.7 mag and a 6 mm exit pupil. A 60 mm EP would give 20.9 x mag with a 12 mm exit pupil. This would suck. How can you get that magnification with a normal exit pupil on a big scope?
In other words, how do you get a bright and wide FOV?
Example: On my 250 mm Dob, a 30 mm EP gives 41.7 mag and a 6 mm exit pupil. A 60 mm EP would give 20.9 x mag with a 12 mm exit pupil. This would suck. How can you get that magnification with a normal exit pupil on a big scope?
In other words, how do you get a bright and wide FOV?