6mm BGO?

[paul mc c]

Would a 6mm BGO be to much power for a 12'' f5.3 dob,would it be worth getting one?

Paul

[spaceboy]

Telescope Optics Formulas with Calculators

[paul mc c]

Telescope Optics Formulas with Calculators

That would give me 265x, would this be usable on only very good nights

[Capricorn]

300*5.3 = 1590, mag = 265x.

Sort of boarderline.

May get to use it occasionally, but not overly often.

Might be useful for Mars in a few weeks time however.

[spaceboy]

I would have said a little too much power and you would be better of spending your money on the 12.5 BGO and barlow it.

[John]

The 6mm BGO is a very sharp contrasty eyepiece but tracking will be hard work at 265x. Might be worth considering something with a wider FoV ?.

If your scope is in good collimation, well cooled and the seeing conditions are good you should be able to use that sort of power on Mars / Saturn / the Moon / binary stars. I use 257x with my ED120 refractor on good nights.

[paul mc c]

That is what i an thinking,that i may only be able to use it on the rare occasion.

[John]

If I recall, your OO dob has very good quality mirrors in it. Top quality optics can make higher powers more useful than in "ordinary" scopes. Seeing conditions have to co-operate too of course

[paul mc c]

Yes John they are the OO Ultra Grade mirrors so they should make a difference.