Eye relief

[Bar]

I have worn spectacles for most of my life and of course the term "eye relief" is important to me.
Some time ago I bought a Tele Vue 17.3mm Delos eyepiece and it is the most comfortable eyepiece to use that I have in my set. It has an apparent field of view of 72 degrees.
Some eyepieces with a metal eye-stop will scratch ones spectacles while trying to observe the entire field: big problem!
The Delos design is a compromise between an eyepiece with a super wide field and a narrower field eyepiece with a large eye relief.
Barry

[Don Pensack]

Over the years, the number of eyepieces compatible with glasses has steadily grown. Tele Vue is one company with significant numbers of offerings for the glasses wearer (Delos, Delite, Nagler T7, etc.) but other companies have addressed the issue too: Baader, Pentax, and many private label brands for the manufacturers KUO, Barsta, JOC and Synta.

If you'd like to see all the possible choices, download the 2025 Eyepieces Buyers Guide and look for eye reliefs of 18mm or more.
https://www.cloudynights.com/topic/959443-2025-eyepieces-buyers-guide/?p=14049961

Here is a discussion of how to measure the Effective Eye Relief of eyepieces, the actual figure that's important to glasses wearers:
https://www.cloudynights.com/topic/837363-effective-eye-relief-a-few-measurements/?p=12093740
It's a fairly long thread.

[david booth]

love the delos range

[refractordude]

Hello There

First thing I want to know is the eye relief before a purchase. One thing I will never understand are these expensive eyepieces with very short relief.

Clear Skies

[JoeBlow]

The expensive eyepieces with short eye relief are usually older designs, often from the 80s and 90s, including many Naglers. Almost all new premium designs from about the last 20 years either have sufficient or long eye relief. If you wear glasses some new designs might feel tight.

[Don Pensack]

Not all observers wear glasses.
People who don't wear glasses often don't like long eye relief eyepieces.
There are plenty of choices with 30-120° fields, and 2mm to 40mm eye reliefs.
Something for everybody.

[m11]

I am starting to enjoy the Delos range of Televue eyepieces as well. I still use Ethos but there is something with the Delos eyepieces that make them enjoyable and found them really sharp. :thumbsup:

[Bar]

on the subject of eye relief again, it is important that all eyepieces have a soft cap at the exit pupil end of the assembly.
I have spent a lot of time making a set of three very large Huygenian eyepieces for the Great Melbourne Telescope. The focal lengths of these eyepieces are 105mm, 150mm and 211mm respectively and their design is bound by heritage restraints.
The original eyepieces had metal caps but the new set of caps have been made on a 3D printer. They are acceptable from a heritage point of view because they look the same as the original components.
Barry

[refractordude]

Hello Don Pensack

"Something for everybody" I agree 100 percent. I do not wear glasses when observing. My Olivon 22mm bested my UFF 30mm. The UFF has good eye relief but the Olivon has a tad bit more.

Clear Skies

[Bar]

It is necessary for some people to wear spectacles while observing. The affliction of astigmatism is one problem that requires the use of glasses while observing.