|
Stopped being so lazy and googled it!
Maximum recommended exit pupil for reflector is around 7mm. Any larger and you might see the shadow of the secondary mirror in the centre of the image.
No such issues for refractors.
Does throw up an interesting issue. With my current f/6 scope, I can go to eyepiece focal lengths of around 42mm. However, if I move to an f/5 scope in the future (which is likely) then the maximum eyepiece focal length would be around 35mm. No point in buying a 41mm Panoptic, then!
Morton
|