PDA

View Full Version here: : Why Kellners for F5 Dob?


ColHut
09-07-2007, 05:46 PM
I wonder if you guys had any idea why Andrews and Bintel sell their 10" & 12" dobs with Kellners - even though Bintel at least say that they don't work very well below F6? Am I not getting something here?

cheers

Wol

Starkler
09-07-2007, 07:42 PM
The 1.25" eyepieces supplied have always been plossls, but the 32?mm 2 inch if supplied is a modified kellner and IMO not very good at f5.

Have they changed their package?

ColHut
09-07-2007, 08:50 PM
Andrews include (with the super deluxe) a "SP32 2" 32mm eyepiece"
which I take it is one of these http:////www.gs-telescope.com/content.asp?id=69 (http://www.gs-telescope.com/content.asp?id=69)
And Bintel offer one of these 26mm Fully Multi-coated Wide Angle or one of these depending on model 32mm Fully Multi-coated Wide Angle
which looks the same asBintel FMC 26mm (2") which again seem the same with http:////www.gs-telescope.com/content.asp?id=69 (http://www.gs-telescope.com/content.asp?id=69)

They offer plossels as well - 1.25" though.

cheers

Wol

Starkler
09-07-2007, 09:54 PM
Thing is decent 2" eyepieces cost serious $ and you cant expect to get them for free with a new dob at the price they sell for.

ColHut
10-07-2007, 12:50 AM
I see you are right - the 65deg 2" Kellners are only $29 whereas a Superview Plossel is $49 at Andrews, and respectively $56-69 for the Kellner at Bintel and a 30mm 2" Bintel Superview is $79.

I take it that at short F ratios the plossels are better?

cheers

Wol

CoombellKid
10-07-2007, 05:15 PM
Why Kellners for F5 Dob?

Because they're cheap and nasty and about all they're good for is give aways.
Actually the ones I have recieved over the years have been dispatched into
the state forest with a tennis racket

regards,CS

Gargoyle_Steve
11-07-2007, 07:53 PM
I hope you used a cheap and nasty racket Rob for that, ;) you don't want to bugger up a good one!

ballaratdragons
11-07-2007, 08:03 PM
And all of those are cheap. Good EP's start around the $120 and go up to around $1000.

Although, when starting out, the GS Plossls are quite good for their price of under $100. I still use mine.