Meade 5000 SWA 40mm

[cyborg421]

Hi All,

I am thing of getting a Meade 5000 40mm SWA for my f4.7 Skywatcher 250 Dob.

Is this a sensible idea or not?

Thanks

Simon

[John]

Nothing wrong with the eyepiece but it's focal length is a bit too much for an F/4.7 scope. The exit pupil that you would get would exceed the diameter of your dilated pupil by quite a margin and therefore you would not be getting the full benefit of your aperture. Something between 25mm and 30mm would be a better bet I reckon.