Which eyepiece? That is the question

[Tris707]

Hi,

Really could do with some advise, I have recently bought a 10" dobs and it came with a 10mm and a 20mm plossel. I have been trying to observe saturn and find although with my meade barlow lens and the wide angle 20mm its very clear, the planet is too small to make out much detail.

I have been looking at the Meade 5000 ultra wide angle lens, but which one? 6.7mm or 18mm.

Any thoughts?

[gedmac]

the 18mm will not make much difference in size as its close to your 20mm ep in magnification,you will just see more of the area around saturn because of the uwa aspect.it will however be a step up in quality from the stock ep.not sure of your focal ratio/focal length of your dob so difficult to comment on the other meade.

[Rusty Strings]

Assuming your dob has a focal ratio of F5, then the 6.7mm would give you a magnification of 187x, which whilst not getting near the the practical maximum, it will show saturn's rings and planet detail. You could go to a shorter focal length (2mm - 4mm) but you will probably find the seeing conditions will keep it in your eyepiece box rather than the scope

[Tris707]

Meant to mention- my telescope is a Skyliner-250PX 10"

[great_bear]

The Meade UWAs are very well-respected eyepieces.

However, the 6.7mm ep falls a little short of the top magnification you should be shooting for, and the next one up is too much magnification. [sigh...] this is often the problem with eyepiece ranges - you can't get one in the focal length needed to get a particular magnification