History of the SW 10mm and 25mm EPs

[Avocette]

I've just bought a SW 250px Dob which the seller said is about 5 years old. Certainly it has a number of differences from a one year old 200p Dob including a rack and pinion focus assembly, but the supplied EPs are very different from the latest ones, are much heavier with much more glass and are labelled Super Plossl. Any SW historians out there who can age them and would you expect them to be better lenses than the modern ones?

[Carbon Brush]

There seems to be a general opinion among users that the 10mm EP quality differs between scopes.

But not having the benefit of lining up several for comparison, I can't really add anything further.

[John]

The ones supplied over recent years are a modified achromat design (3 elements in 2 groups). The 25mm is labelled "Super Wide" although it's not really but they don't have "plossl" on them because they are not that design. The Super Plossls with your scope are a very similar to, or the same as the SP plossls here:

http://www.firstligh...-eyepieces.html

It's possible either that a previous owner replaced the originals with these plossls or that a dealer decided to supply the scope with slightly better eyepieces when it was sold new, perhaps as a promotion ?

The SP plossls are a bit better than the modified achromat designs.

[Stargazer_00]

The ones I got with my 350p recently are higher quality than the ones I've had previously. heavier and better built. seemed better optically too.

[Avocette]

I've now taken some photos but can't seem to attach/insert them.

[John]

Use the "more reply options" button at the bottom right - that gives you the "Attach Files" facility below the extended text entry box.

Photos really do help in identifying eyepieces - many plossls / modified achromats look pretty similar !

[YKSE]

John, are these MA eyepieces more like Kellner or RKE in design?

[John]

John, are these MA eyepieces more like Kellner or RKE in design?

More like the Kellner I think. The RKE has the doublet and singlet lenses the other way around I believe and the doublet field lens is concave on the scope side.

[Avocette]

Here are the photos (thanks John) -