Widefield EP question

[Manok101]

I'm considering instead of a new telescope getting a widefield EP less than 20mm, and I was wondering if it were worth it and if they even made EP that small?

[LukeSkywatcher]

For widefield you want to be looking at buying a 30-32mm Plossl with a FOV of about 50 degrees.

Superb EP's.

[perrin6]

If it were me I'd rather get a new telescope than a new eyepiece, but that's me !

[swamp thing]

What scope is it to be used with?

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[great_bear]

I'm considering instead of a new telescope getting a widefield EP less than 20mm, and I was wondering if it were worth it and if they even made EP that small?

"Widefield" falls into four loose categories I find:

58-60 degree AFOV

68-70 degree AFOV

80-82 degree AFOV and

100-110 degree AFOV

Tele Vue sell models that cover all four categories in sub-20mm lengths. Pentax have a nice range, the XWs, although the 20mm and 14mm have field curvature issues. Nikon do a couple of very expensive ones.

The above are the only ones guaranteed to work well in all scopes, but if you are on a budget and don't wear glasses, the Meade SWA 16mm is a superb model at a good price here, and one of my most-used eyepieces.

Explore Scientific are another option here, but steer away from any of the 70 degree Explore Scientific ones on that page, as those particular 70-degree ones are not good choices.

[Capricorn]

William Optic's SWANs come in 20mm, 15mm and 9mm and have a have a 72 degree field of view.

Think that they are not recommended for scope of less the f/6 which may be a problem.

[Manok101]

I am considering between 10-15mm for my 10" dob. I think the dob has about a 5 on the focal length I'd have to recheck that though. I do wear glasses but ha ve not had trouble with eyepieces in the past.

[swamp thing]

Hi

In my 10" f/4.5 I use a 12mm T4 Nagler.

Not the cheapest or the lightest eyepiece by a long way.

It does have great eye relief and a lovely big eye lens though, so a pleasure to use.

It Is also razor sharp across the entire field.

Regards Steve

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[great_bear]

I am considering between 10-15mm for my 10" dob. I think the dob has about a 5 on the focal...

Yes, pretty much - it's F4.7, so it will give most widefield EPs a bit of a spanking. You're really in Tele Vue territory here: Remember that Tele Vue's entire business was built on providing eyepieces for big fast Dobs, because no-one else does so - at least to the same degree of quality.

All Tele Vue EPs are tested down to F4; most other people's eyepieces bottom out at F6.

They're pricey it's true - but in a whole different league than cheaper eyepieces.