How good are the GSO 1.25" Super Plossl eyepiece

[Baron von Richthofen (Vaclav)]

Hi All
How good are the GSO 1.25" Super Plossl eyepiece compared with the Meade 4000 series 1.25" Super Plossl eyepiece
I am going to use them for casual viewing
Vars

[Kal (Andrew)]

What scope? A fast F4 reflector or a long focal length F10 cat? The scope can have a big impact on the usefulness of a type of eyepiece.

[wavelandscott (Scott)]

The GSOs are generally pretty decent eyepieces. There are some other brands that are better but much more expensive.

GSO Plossls came with my first scope and they kept me happily entertained for quite some time. I've not tried the Meade 4000 series and I am not certain if the Super Plossls are what I have or not....my goods are enroute from Australia to the US where my company has recently transferred me. If you don't get much response here or IIS that is useful give the folks at Bintel in Sydney a bell...I'm sure they will point you in the right direction.

Cheers,

[Baron von Richthofen (Vaclav)]

It is a ED80 F7.5

Hello Vars,

"symmetrical Plössl" type eyepieces like the GSO will work quite good with
a f/7,5 telescope like yours.
When you center a sufficiently bright star in the center of the field of view
and then let him drift towards the edge you will realise that the star gets
slightly deformed. Most of it will be due to field curvature of both your
telescope and the eyepiece. Like this: )(
You can check it by refocussing at the edge. The younger your eyes
the less need for refocussing since your eyes will do this.

There are other aberrations besides. The simple eyepieces like Plössl, RKE,
Kellner, Abbe Orthoscopic will show astigmatsim at the edge when used in
fast telescopes.
Your f/7,5 is in between of fast and slow and I guess that the Plössl will
be o.k.
You can add a quality barlow and get rid of all edge performance issues.
A quality barlow barlow may be a good part too for reaching high magnifications.
Your scope will be useful up to 120x and you would need a 5mm Plössl for this.

A 5mm Plössl will have about 3,5mm eyerelief (focal legth x 0,7).
This is very short. A 10mm Plössl will provide about 7mm eyerelief,
wich is sufficiently comfortable (but not very vomfortable) for me.

Hope this helps you a little bit, Karsten