Barlow/Powermate with Star71

William Optics Star 71 Barlow Solar System
WO Star 71 •2 replies•84 views
Mike Miller avatar
Mike Miller avatar
Has anyone tried a Barlow or Powermate on the Star71 for lunar/planetary?

I tried a cheap 2x Barlow I have and was not able to focus due to it taking too much back focus. I wonder if a Televue Powermate would be more successful.

I also am thinking about trying a Canon EF 2x teleconverter. I would expect something for that would noy increase backfocus at all since it's designed to fit in between a camera and a lens.
Engaging
Samara avatar
Samara avatar
Never tried. This is the last OTA I'd use for planetary, it's just not made for it.
MGralike avatar
MGralike avatar
For what its worth, and more here for people to read / as a reference... I didn't succeed with any of my Baader barlows but did with the TV Powermate 5x I have, at least when using visual (using the WO prism for the Star71)...

I did use a 2.25x Baader Barlow to photograph the moon though... 

https://www.astrobin.com/358363
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