GSO 2" Kellner Eyepiece - 26mm # GSK26

5.0 Great eyepiece

Quality Lenses

None

I purchased this Kellner to fill a gap in my 2" eyepiece collection. Quite frankly, I did not expect much from this eyepiece. Once I received it and used it, I was very pleasantly surprised! The views and contrast are great and outperforms eyepieces that are substantially more expensive. I wish that GSO would make a complete set of 1.25" Kellners of similar quality; I would buy them instantly. I highly recommend it.

This review was provided courtesy of AgenaAstro.com

5.0 Great Value

Quality Lenses,Accurate,Strong Construction

A great upgrade for a Classic C8. Amazing how much larger the field of view is. Seems to be a very high quality lens.

This review was provided courtesy of AgenaAstro.com

4.0 Ideal for the faintest DSOs (GSO 26mm Kellner)

Bright images. Generous field of view. Lightweight.

Typical Kellner aberrations. GSO should dispense with barrel notch/indent and just use smooth sides.

Kellners really deserve a second look even by the more experienced amateurs. Their strength lies in producing (at least) fairly decent views with as few glass elements as possible. What this means in practical terms are brighter views of deep-sky objects than with other eyepiece designs.

I am more or less confined to a severely light polluted location. Yet with this eyepiece and an 8" f/6 dobsonian telescope I've finally been able to see M33 as well as several other faint galaxies and nebulae at the limits of viewing that were dimmer or invisible in other eyepieces.

The 2" 65 degree eyepiece is a real plus compared to the narrow fov of conventional Kellners.

The only real negative in this eyepiece is the barrel notch/indent that is designed to keep the eyepiece from falling out accidentally, ends up making it a fussy affair to remove the eyepiece from the focuser when changing. This is GSO's decision apparently.

Some would argue that a Kellner such as this would be best suited for a long focal length telescope. And it's true that at f/6 there is field curvature and lateral color towards the edges. This is not a first choice for viewing *bright* DSOs like the Double Cluster, let alone the Moon or planets. HOWEVER, for faint nebulae or galaxies, this is a winner.

4.0 Excellent for viewing very faint DSOs

Strong Construction,Lightweight,Compact,Quality Lenses,High transmission

Fussy 2 remove at focuser

I have discovered that Kellner-type eyepieces are outstanding for viewing very faint objects at the limits of visibility. From my light-polluted (red/white zone) skies I finally was able to see M33 with this eyepiece and an 8" f/6 dob.

A real plus is the 2" format and 65 degree fov.

My only negative (and it is minor) is the indentation designed in the barrel to keep it from falling out accidentally. It makes it very hard to determine how much to unscrew the capture screws in the focuser without unscrewing them entirely when removing the eyepiece. I'll unscrew a little here, a little there, pull up on the eyepiece, and it still won't come out without fiddling with it more. This is not unique to this eyepiece but seems to be common with some manufacturers.

Of course, at f/6 a wide field Kellner is not going to be the best performer on planets or star clusters, with some distortion towards the edges. But for the specific purposes that I strongly recommend, which is for viewing faint galaxies and nebulae this eyepiece deserves a closer look. A keeper.

This review was provided courtesy of AgenaAstro.com

4.0 Low cost , high quality lens and case

Accurate,Quality Lenses,Strong Construction,Compact

Best components, is very cheap, the lens and the case are very good. I am satisfaction

Sorry for my english

This review was provided courtesy of AgenaAstro.com

4.0 GSO 26mm Kellner

Sharp well coated optics,Quality look and feel,Excellent price

None

I decided to buy the GSO 26mm Kellner based on my purchase of the 32mm version of this eyepiece. This eyepiece did not disappoint me. The quality of workmanship and materials is very good and the optics are very sharp with the nice green multicoatings.

These Kellners seem to have a much brighter and sharper image compared to Plossls and such. They feel good in your hand and look good. It is hard to imagine how they can make this eyepiece for the price! After reading the other review I inspected the inside of my 26mm for any imperfections and found none.

This review was provided courtesy of AgenaAstro.com

4.0 GSO 26mm Kellner

Very good optics,Solid construction,Good eye relief

Paint flaking inside

After enjoying the views through a GSO 42mm ocular, I decided to give the 26mm Kellner a try. This is a 3-element design, with fully multi-coated optics and blackened lens edges. Eye relief is a comfortable 20mm, and the 2" barrel will accept standard 48mm filters. This inside barrel of this particular unit was not evenly blackened and showed some bright areas where the paint had flaked off. I was concerned about possible light scatter, but for the price, I just decided to respray the inside of the barrel myself and go with it. I was rewarded with some fantastic views of star clusters and nebulae, with pinpoint stars up to maybe the last 5% of the field of view. Light scatter worries appeared to be unwarranted. The eye relief was a godsend and only made the views more enjoyable. I might mention that these observations were made using a Celestron C80ED f/7.5 refractor with a William Optics 2" 90 degree diagonal. I really like this eyepiece and it fills a gap between my 30mm and 15mm 2" UWA eyepieces. Once again, Guan Sheng Optical has produced another winner.

This review was provided courtesy of AgenaAstro.com

4.0 GSO 26mm Kellner

Solid construction,Very good optics,Good eye relief

Paint flaking inside

After enjoying the views through a GSO 42mm ocular, I decided to give the 26mm Kellner a try. This is a 3-element design, with fully multi-coated optics and blackened lens edges. Eye relief is a comfortable 20mm, and the 2" barrel will accept standard 48mm filters.

This inside barrel of this particular unit was not evenly blackened and showed some bright areas where the paint had flaked off. I was concerned about possible light scatter, but for the price, I just decided to respray the inside of the barrel myself and go with it. I was rewarded with some fantastic views of star clusters and nebulae, with pinpoint stars up to maybe the last 5% of the field of view. Light scatter worries appeared to be unwarranted. The eye relief was a godsend and only made the views more enjoyable. I might mention that these observations were made using a Celestron C80ED f/7.5 refractor with a William Optics 2" 90 degree diagonal.

I really like this eyepiece and it fills a gap between my 30mm and 15mm 2" UWA eyepieces. Once again, Guan Sheng Optical has produced another winner.

This review was provided courtesy of AgenaAstro.com

5.0 GSO 26mm Kellner

Quality look and feel, sharp well coated optics, excellent price.

None

I decided to buy the GSO 26mm Kellner based on my purchase of the 32mm version of this eyepiece. This eyepiece did not disappoint me. The quality of workmanship and materials is very good and the optics are very sharp with the nice green multicoatings.

These Kellners seem to have a much brighter and sharper image compared to Plossls and such. They feel good in your hand and look good. It is hard to imagine how they can make this eyepiece for the price! After reading the other review I inspected the inside of my 26mm for any imperfections and found none.

4.0 GSO 26mm Kellner

Solid construction; Good eye relief; Very good Optics.

Some paint flaking on the inside barrel of this unit.

After enjoying the views through a GSO 42mm ocular, I decided to give the 26mm Kellner a try. This is a 3-element design, with fully multi-coated optics and blackened lens edges. Eye relief is a comfortable 20mm, and the 2" barrel will accept standard 48mm filters.

This inside barrel of this particular unit was not evenly blackened and showed some bright areas where the paint had flaked off. I was concerned about possible light scatter, but for the price, I just decided to respray the inside of the barrel myself and go with it. I was rewarded with some fantastic views of star clusters and nebulae, with pinpoint stars up to maybe the last 5% of the field of view. Light scatter worries appeared to be unwarranted. The eye relief was a godsend and only made the views more enjoyable. I might mention that these observations were made using a Celestron C80ED f/7.5 refractor with a William Optics 2" 90 degree diagonal.

I really like this eyepiece and it fills a gap between my 30mm and 15mm 2" UWA eyepieces. Once again, Guan Sheng Optical has produced another winner.