Which barlow / telextender would be best?

[Stargazer51N]

I have a 150, 1200, f8 reflector on driven EQ mount and am just starting out imaging Jupiter using an SPC900. I have a Tal 1.5x Barlow which works ok but I'm after a larger image. I have read many posts on the subject of barlows but I am confused ...

Would I be better off aiming for f20 using a 2.5x or f24 using 3x?

I've shortlisted the following, which would you choose?

1) Revelation Astro 2.5x Barlow 1.25" - £31

2) Meade series 5000 3x telextender 1.25" - £90

3) TeleVue 3x Barlow 1.25" - £87

Oops .. 1st go at a poll and I've ended up with the options in the post as well!

[brantuk]

I clicked the TV but the Meade will give it a good run for it's money. For me however you don't list the best ones - TV Powermates are just awesome - you don't even know they're there - but correspondingly dearer - you'd never buy another one though

[Stargazer51N]

Thanks brantuk. In your opinion would I get better results with a 2.5x Powermate giving me f20 or a TV 3x Barlow giving me f24? If I went for the Powermate would I be able to also add my Tal 1.5x Barlow to give me f30 (or would that be pushing my scope too far?)

[riklaunim]

If you don't need stable or almost stable magnification vs distance to the camera then choose good 3-element Barlow (like GSO/Revelation). I use Meade TeleXtenders as I need the stable magnification. They do work but they also do have some design issues

[dweller25]

I used a Klee x2.8 Barlow in my Newtonian and it gave excellent results.

[brantuk]

I never tried double stacking barlows - but I'll have a look at that next time I'm out - if this weather ever gives us a chance lol. As for whether to use a 2.5x Powermate or a 3x TV barlow - I'd allways go for the appropriate Powermate.

The TV barlows are good mind, but they work differently to the Powermates - I can't explain it technically yet till I've re-read and digested my Powermate instructions again

That's not to say other barlows are ineffective - It's just that I got my first Powermate recently and am totally sold on it right now lol.

[Stephen]

Once you go Powermate, you're doomed to the green

[beamish]

the problem with the Meade is surely the "grenade" size??? I'd suggest TV

[riklaunim]

2x has long nose which may not fit to every eyepiece holder nicely. 3x in my case has some back-reflections on Moon or Sun if used with interference filter before it.

Those TeleXtenders have been killed and new version are now made as Bresser SA Barlow. It seems they changed the shape a bit.