Mid-20s Focal Length Eyepiece for Eye Glass Wearer

[DeepSkyMan]

Hi there I am searching for an eyepiece in the 82 degree AFOV arena suitable for eyeglass wearers.  I have astigmatism (Left -3.25, Right -2.25) left eye is dominant.  I really like the look of the 26mm Nagler T5, however it's listed as 16mm eye relief, and I have some concerns that this might not be sufficient ER for my use.  Anybody out there ever used the 26mmT5 with eye glasses?  If the T5 isn't going to do the job, can someone recommend a suitable alternative?  I already have the Televue 32mm Plossl and had thought about the 31mm Nagler T5 as a potential replacement, however the 32mm is a recent purchase and I would prefer to hold on to it for a while yet.  Telescope is an 8" EdgeHD.

 

Kind Regards

Paul J.

[Louis D]

I have slightly less astigmatism than you, so I'm in a similar boat.  Here's my experiences:

I use the 70 degree 22mm Astro Tech AF70 with eye glasses in that range.  Very comfortable and easy to hold the view.  It is sharp up to the last 5 degrees, so it runs quite well with my Naglers, Delos, XLs and XWs.  It is available under the Olivon and many other brand names.

I tried the 22mm Nagler T4, and it is difficult to take in the whole view without mashing your eyeglasses into it.  I have the 12mm and 17mm versions, and both are tiring to use with eyeglasses though they are quite sharp to the field stop.

I have the original 30mm ES-82 with the flush mounted eye lens like the Axiom and Meade 5000 versions.  I can just take in the whole field by mashing my glasses into the top.  It's easier to hold the view than the in the T4s, but not nearly as sharp to the field stop.

I also have the 27mm Panoptic.  It is nearly sharp to the field stop, but the eye relief is similar to the T4s, maybe a little more.  It is not tiring to hold the view, but the exposed retaining ring at the top has scratched my eyeglasses in the past.

I've also used my 40mm Meade 5000 SWA in a telecentric 2X barlow to good effect.  Huge, long, and heavy, but it works well and has over 25mm of eye relief with the eyecup structure removed.  I've measured the AFOV to be 71 degrees via projection, so it's pretty wide.

Unfortunately, that range of focal lengths doesn't offer much to the astigmatic viewer in very wide fields.  Maybe ES will extend their ES-92 line above 17mm.  Don Pensack on CN said that they will be coming out with 3 new focal lengths soon.

[DeepSkyMan]

Hi Louis, thanks for your feedback.  I think I might just give the 22T4 a blast.  I have the 17T4 winging its way towards me from a sale on CN, still a couple of weeks away though (surface mail unfortunately), guess the thing to do would be to wait until the 17mm arrives, hopefully to be followed by some clear sky's to try it out, and see how they match up with my glasses.  I was going to target the Delos range, which would solve the ER issue, but I really wanted to experience the ultra wides first, see what all the hype was/is about.  If I don't fare well with the T4s then I can always fall back on the Delos range (never to sure about the plural for Delos... Lol).

 

Kind Regards

Paul J.