Whats the widest eyepiece you can use with a Orion OMC 200

[Heavens Above]

Anyone tried using a 32mm 50 degree or similar eyepiece with an Orion OMC200? Do you get any vignetting or darkening at the edges of the field of view. Guess I am asking what is the lowest practical power of this scope without vignetting?

Thanks

[John]

According to the spec it has an optical back of 31.7mm so I guess you are limited to 1.25" eyepieces. In that size the following show about the most sky in that fitting:

- 35mm Ultima (used if you can find one) - 49 deg AFOV

- 32mm Plossl - 50/52 deg AFOV

- 24mm Super Wide (eg: Panoptic, Hyperion) - 68 degree AFOV

- 20mm Ultra Wide (Widescan III - a bit unusual) - 84 degree AFOV

- 18mm Ultra Wide (eg: Meade UWA) - 82 degree AFOV

The best you are going to do is .43 of a degree of sky @ 114x because of the F/20 focal ratio.

Unless there is a focal reducer available for the scope ......

[Stu]

Hi,

If still relevant, the OMC200 has a 2" adaptor available which means you are not limited to 1.25" ep's. I regularly use a WO 28mm and occasionally a 41mm Panoptic which I think gives a 0.7 degree field of view. I don;t notice significant vignetting with it

Stu