Skywatcher 250px Dob and TMB 6mm Planetery?

[George!]

I was going to buy the TMB planetary 6mm eyepiece from someone here but since I now have the 250px would it be a very bad discussion since it's F4.7.

Please be honest,

[Moonshane]

I am not sure what the focal ratio is as on FLO it says f5 but states the focal length is 1200mm and the aperture 254mm (which equals f4.7) and on Rother Valley it states the same measurements but also states f5.91!.

assuming it is f4.7 or f5 then whilst the TMB should be OK in your new scope it would possibly perform better in scopes at f6 or more.

that said, you may well be very happy with it. the eyepiece will give a mag of 200x which is probably fine most of the time on the moon and doubles and sometimes planets. I find the 'peak' mag for planets is about 150x and occasionally up to 225x.

what other eyepieces do you have?

[GazK]

I use a 6mm TMB with my 10" dob and the views are OK. I'm sure it's not in Nagler territory but then neither is the price!

[kniclander]

i use the 5mm and the 8mm in my 10" dob but mostly the 8 as the 5 tends to be pushing the mag a bit. I suspect that unless you are used to "premium" e/ps you will be more than happy with the tmb clones.

[mcooke999]

I've owned the 250PX and used it with my TMB 6mm EP and it gave fantastic views of the moon and jupiter.

[spaceboy]

I had a 4 & 5mm TMB clone and while I have a 250PX I only used them in my 200P F/5 in which the clones performed superbly for such a cheap EP. What you must remember is high magnification means more nudging and if the seeing isn't at it's best this could mean you never really get an image worth looking at.

[George!]

Will it be hard to find Jupiter etc and is there really any clearer between the 6mm and a 10mm with a 2x barlow?

[John]

A 6mm TMB planetary will be much better views than the standard 10mm used with the standard barlow lens, if thats what you mean.

[George!]

A 6mm TMB planetary will be much better views than the standard 10mm used with the standard barlow lens, if thats what you mean.

Yeah, I was going to buy a second hand imaculet Celestron Ultima Barlow of someone here also.