The Celestron Super Plossls are no longer manufactured. I was so lucky that I had the chance to borrow 4 of them from Antony Allsobrook, NZ for thesting them with two different Newtonian scopes. In a previous post I gave some preliminary statements based on the experience using an 8-inch f/6 Portaball. Now I also had the chance to try them with a 12.5-inch f/4.5 NGT.
The Celestron Erfles come with focal lengths 16, 20, 24, 28 and 32mm (all 1.25") and I tried all except the 32mm. In my opinion all are great eyepieces. The field of view is somewhere in the 65-70 degree range, and the image is bright and sharp. With the f/6 scope all eyepieces were sharp to the edge, and at 43x power double stars with 4" separation were split. Using an O-III filter the 28mm gave beautiful images of objects like the Veil and North America nabula.
With the f/4.5 images were still decent, but when focusing on an object near the centre, the edges became slightly unsharp. Once noticed, this was a bit annoying.
The eye relief of these eyepieces permits observation with glasses, but still I experienced no blackout problems. In my opinion they are GREAT eyepieces for low power use with scopes with f/6 focal ratio. With faster scopes, there may be a need for a coma corrector.
The Celestron Erfles come with focal lengths 16, 20, 24, 28 and 32mm (all 1.25") and I tried all except the 32mm. In my opinion all are great eyepieces. The field of view is somewhere in the 65-70 degree range, and the image is bright and sharp. With the f/6 scope all eyepieces were sharp to the edge, and at 43x power double stars with 4" separation were split. Using an O-III filter the 28mm gave beautiful images of objects like the Veil and North America nabula.
With the f/4.5 images were still decent, but when focusing on an object near the centre, the edges became slightly unsharp. Once noticed, this was a bit annoying.
The eye relief of these eyepieces permits observation with glasses, but still I experienced no blackout problems. In my opinion they are GREAT eyepieces for low power use with scopes with f/6 focal ratio. With faster scopes, there may be a need for a coma corrector.
