GSO SuperView 42mm 2" wide angle eyepiece ERFLE 42mm - 60° field of view

TS Optics WA ERFLE eyepieces offer a very good quality for an affordable price. Direct import from the factory allows us to offer them so cheaply without sacrificing quality!

Specifications and Features of the WA Erfle 42mm:

-- Focal Length: 42mm
-- Field of view: 60°
-- Coating: fully multi-coated
-- Blackened lens edges: yes
-- Field stop diameter: 47mm
-- Eye relief: ca. 20mm
-- Barrel diameter ... 2" with filter thread
-- Optical layout ... 5 lenses in three groups (Erfle design)

This eyepiece is recommended for the following telescopes:

-- Newtonians with f/6 or longer
-- Refractors with f/6 or longer
--- All other telescopes with 2" focuser

A short comparison: WA Erfle 42, Panoptic 27, Wild 30

Aside from field correction and sharpness you should also compare other properties of eyepieces. Transmission is one point that is very important for Deep-Sky use, but without properly blackened interior and baffling any eyepiece will throw up bright images with a poor contrast.

You can easily do the test yourself:

Just put the eyepiece on a dark surface and take care of good lighting conditions (daylight). Then look onto the front lens from an angle of about 45°. The brighter the lens surface you can see, the more stray light exists inside the eyepiece. This stray light will diminish contrast.

You can see that the eyepiece on the left produces a lot of stray light. Coating and baffling are poor. When compared with the Panoptic or the TS WA the background of the image rendered by this eyepiece will be brighter, resulting in reduced contrast.

Both the TS WA and the Panoptic are much darker, you will have a noticeably better contrast when you look through these eyepieces. When it comes to the blackened interior of the eyepiece body these two eyepieces very closely match one-another.

To be fair with the 4x as expensive TeleVue Panoptic, though, this eyepiece has other advantages when compared with the TS WA. It can be used in very fast Newtonians down to f/4 with good field sharpness. When you compare image clarity and contrast the TS WA will perform nearly as well as the Panoptic.

in the first week of September I had the opportunity to intensively test the new eyepiece at ITH in Reinsehlen. We had an exceptional observing night I spent with my Lichtenknecker 6" f/15 refractor. Same as in an earlier quick test I was positively surprised by the image quality.

Eye relief is very comfortable, even with eyeglasses. The image is crisp and free of internal reflections, the field of view feels as large as advertised. At the resulting 45x magnification the east half of the Veil nebula fitted well inside the field of view and just touched the edges. With a 2" UHC filter it was a phantastic view!

In order to test the image sharpness towards the edge I had a look at a populated area of the milky way. At the extreme edge of the field a small amount of coma could be seen, which however was not distracting (at least for me).

I also liked the mechanical quality of the eyepiece very much.

All in all I am very happy with this eyepiece so far!

Greetings from the North,

Michael Kießling.