Since no one has replied I'll put in 2 cents worth:

The Edge has a fairly flat and well corrected field,?similar to a?quality refractor. You want an EP that does?not correct for coma.? EPs that do well on good refractors should also work well with an Edge.?

I?generally favor a TeleVue EP (unless?the?specifications suggest correction for Newt or traditional SCT).?? But I don't look thru my scopes all that much anymore (mostly do imaging).

Stan

All,

I think that there are many situations where non-ideal viewing conditions limit the effectiveness of upper end eyepieces especially for 67 year old eyes?That being said I do have three Tele?Vue Ethos for my C-11. For wide?field viewing I really like the Orion q70 38mm. At only $99 it's a great bargain.

regards,

Ron K.

There are a few problems with trying to use a large aperture for visual wide field, primarily exit pupil and the extent of the corrected field.

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Exit pupil is the diameter of the parallelized light exiting the EP and trying to enter your eye.? If the?exit pupil is larger than your eye's iris then most of the light will fail to make it thru.? Furthermore, if the scope is obstructed (as SCT is by the secondary) then you will experience unpleasant?shadow effects?that are extremely sensitive to exact eye placement.? So unless you are imaging or using an intensifier (for live viewing) then there is a strict limit on the FL and magnification that can be used with the scope.

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Exit pupil = EP_FL / f-ratio

dark adapted eye iris diam = approx. 8mm (varies somewhat by individual)

magnification = scope_FL / EP-Fl

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So the?longest EP FL usable with that scope is about?80mm?for a minimum magnification of 35x.

Thus?all?the EPs you list are OK and you could get a lower magnification (via longer FL EP) if you wanted.

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However, magnification is only part of the story, especially for expensive very wide field EPs.?If the EP's true FOV exceeds the scope's corrected field then the perimeter of the view will be poor (e.g. excessive coma, astigmatism, defocus, etc.).? The Edge is?corrected for?FOV somewhere near 30mm(?).?The math gets a bit more complicated but a simplification is:

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linear FOV = L / fl (where L is the angular FOV in radians and fl is the optic focal length)

so for linear FOV = 30mm with fl = 2794mm:

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angular FOV = 30/2794 = 0.011 radians = 0.6 deg (larger than the moon but not by much)

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finally, the formula for converting EP apparent FOV to angular FOV is:

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angular_FOV = apparent_FOV / magnification

or

apparent_FOV ?= angular_FOV * magnification

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So if you choose a 40mm EP (e.g. Panoptic 41) then:

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Magnification = 70x

Exit pupil = 4mm (plenty good enough)

Corrected angular FOV = 0.6 deg

Maximum useful apparent FOV = 42 deg

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The Panoptic 41 Panoptic 41 has apparent FOV = 68 deg, thus it is overkill and the periphery quality will be poor.? However, your eye’s periphery is not so good anyway and you might like the “space walk” experience even if the edges are not really in focus.? But you could save some money by getting a more modest EP and not loose much in the way of actual quality.

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Stan

P.S.??An alternative?to consider is to get a shorter FL with a wide field. The magnification will be greater but the corrected angular FOV will be about the same as the Panoptic 41 Panoptic 41.? I like wide?FOV EPs in the 12-24 mm range.? But beware of overly short EP FL because the optimal eye distance?(relief) may be short and overly critical.

Reflections are not necessarily from the EP. Check the diagonal and everything in the image train for any unblackened surface. Also check the EP; you might be able to fix the problem.

I recommend?a high quality wide field EP in the range of 25-35mm. Buy?from Orion or other retailer that allows return for full refund.

Stan

Personally I'd go with a Televue 41mm Panoptic or a 31mm Nagler. They have basically the widest FoV of any eyepiece in a 2" barrel, with the 41mm very slightly wider. Televue has an eyepiece calculator on their website that gives all pertinent info as regards their own eyepieces on any OTA. Advantage of the 31mm Nagler is that it gives higher magnification (darker background?), but some may find the 82 degree apparent FoV too wide with the 65 degree AFoV of the Panoptic more cosy. I suspect that since Al Nagler is so passionate about his eyepieces, their image fields are quite flat and hence suited to the Edge HD. But that really needs confirmation from somebody who has actually used them on said scope. Perhaps try asking on Cloudy Nights?

In my opinion the BEST QUALITY full view is with the 31mm Nagler T5, its only .91-degrees but its well corrected right to the field stop. Plus its 82-degrees instead of 68. You get almost the same FoV, but with more magnification (90x) and a darker sky.

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