Interactive Sky avatar

Hi everyone,

I’m currently imaging with a Celestron SLT 130 (650 mm, f/5) and ASI662MC, and I’m thinking about adding a Barlow / focal extender to increase image scale for small targets.

I’m considering the Tele Vue Powermate and Explore Scientific Focal Extender.

If you’ve used either of these, I’d really appreciate hearing your experience with the image quality (sharpness, star shapes, etc.) in real-world use.

Thanks in advance! Clear Skies!

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andrea tasselli avatar

I very much doubt that a barlow is going to help you (like ever!) but if I were to chose one I’ll opt for the TV PM 2x any time.

Interactive Sky avatar

Thank you, Andrea.

Clear Skies!

Werner Stumpferl avatar

Add one for TV PM

Pete Bouras avatar

I have the 2” ES Focal extender 2x. Works great, used it with my 8” F/7 Newt for lunar images. Nice crisp images and my Newt has no field corrector, but I was using smaller cameras as well so coma was not really a problem.

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