Another eyepiece question

[Johnboy]

Hi everybody,

I will be getting a bonus from work shortly and have decided to buy a decent eyepiece to go with my 12" Lightbridge. At first I had pretty much decided on a 13mm Ethos as there doesn't seem to be any bad reviews for them, but as I have perused the threads I have noticed the William Optics UWAN eyepieces are very highly regarded. Apart from the differences in price and FOV, are there any other things about the Ethos that make them worth the extra cost? I believe they are well corrected for use with an F5 scope such as the Lightbridge but are the UWANs? Also if I decided on the UWAN, I would possibly buy two to use with my binoviewer. Is there a limlit with binoviewers regarding FOV? There wouldn't be much point buying two eyepieces with an 82 degree FOV if the binos couldn't show the full field.

Many thanks in advance for your replies,

Best regards

John

[brianb]

Also if I decided on the UWAN, I would possibly buy two to use with my binoviewer. Is there a limlit with binoviewers regarding FOV?

Ultra wide EPs tend to be rather wide in diameter, they may well be too fat to use in a binoviewer as you will not be able to adjust the inter eye distance close enough. Suggest you check this before investing in any EPs you intend to use with a BV.

[Johnboy]

Thanks Brianb,

That's an excellent point. I'll certainly check that.

regards

John

[John]

The UWAN's are very good - pretty much 95% of the performance of a Nagler but at less cost. The Ethos is another step up again though IMHO and not just in it's wider field of view.

Tele Vue slimmed down the Ethos 13mm design after the initial production run because they were proving a little "tubby" for use in binoviewers - this is only of benefit to those with the budget to buy them in pairs of course !.

The Nagler Type 6's and the Type 5 16mm are slimmer than the UWAN counterparts.

John

[gliderpilot]

I bought two of the slimmer 8mm ethos (is that ethi?) for use with a binoviewer on a trip to the US last summer when the exchange rate was extremely favourable. Unfortunately the large barrel sizes meant I could not physically look through the eyepieces so one was sold on.

What binoviewer are you using?

Mark

[Johnboy]

Hi

Thanks for your replies - they are very helpful. I am using a William Optics binoviewer. The 20mm SWAN's that came with it are very good, hence the reason for considering the UWAN's. I do enjoy using both eyes, but a single Ethos is so tempting. I'm just not sure whether a binoviewer is capable of taking advantage of a wide angle view. I'm sure I read somewhere that anything over a certain FOV in the eyepieces is wasted because there is a 'cut off' point which the binoviewer just doesn't use. Hope that makes sense!

Thanks again,

John