2" Kellner EP's or zomm EP's

[Maximillion]

hi all

i have been looking for a while and have came to the conclusion that i would like to buy either a 2" Kellner EP or a the skywatcher 7-21mm zoom EP. i have never used these eyepieces before so what are your opinions on these eyepieces. they are both roughly around the same price so which one would give me the best optics.

regards

[brianb]

Kellner eyepieces give good results with slower scopes (up to about f/7) but orthoscopics or plossls are usually better - wider field, and Kellners are prone to "ghosts" from internal reflections of bright objects which makes them particularly poor for planetary work.

I never found a zoom eyepiece that I would consider as good as a normal eyepiece I could get for 1/3 the price ... and the SW zoom is not, in my experience, a good example of the family of zoom EPs.

I wish I could give positive advice but you don't say which scpoe you will be using the EPs with, or what you want to view with them. Your choices are contradictory as a 2" Kellner would give low power views whereas the zoom EP would give medium to high powers (with most scopes ... insanely high with some).

[sixela]

What scope do you have and what's your budget?

[Maximillion]

thank you for the reply. that has helped and the scope i am using at the moment is a skywatcher skyliner 150p (6 inch dobsonian)

[sixela]

For an f/8 Dob, the cheapest more or less pleasant 2" eyepieces are the Kunming United Optics SWA's, sold as Orion Q70, Skywatcher Panaview, Teleskop Service WA and under other names. They come in 26/32/38mm focal lengths. In that scope I'd certainly get the 38mm (or the 32mm if you want to save ten pounds).

If you have a larger budget the Skywatcher Aero is worth a look, and so is the Meade 5000 SWA now that the liquidation sale is in full force (search Telescope experts Astroshop for 'wide fishes').

As far as zooms are concerned, you have the Hyperion zoom and the ubiquitous Chinese 7-22mm zoom as cheaper fairly good zooms, but they're not as good as single focal length eyepieces.