Affiliation
None
Mon, 06/17/2019 - 13:30

  I was wondering if any members have had experience using binoviewers and which ones they'd recommend. I cquired a nice 6" f/6.5 wide field refractor last year, and I'm hoping to find a good (and hopefully not too expensive) binoviewer that would work with it. I'm thinking this would make it excellent for visual variable star estimates.Thanks in advance! 

Affiliation
American Association of Variable Star Observers (AAVSO)
Have you been to Cloudy

Have you been to Cloudy Nights?, they have a forum for Binoviewers. Great web site with valuable and interesting topics.

Affiliation
None
Visual Observing With Binoviewers

Perhaps I should re-phrase my question. I guess what I really wanted to know is if any other AAVSO members routinely use a telescope with binoviewers to make visual estimates. I would like to try it, but I understand that there might be some light-loss by splitting the image. I also understand that using both eyes to make estimates might compensate for any loss of light. Thanks in advance.

 

Affiliation
American Association of Variable Star Observers (AAVSO)
Binoviewer frustrations

I own William Optics binoviewers and have used them for some of my variable star observations. Field of view, however, is a problem. The size of the prisms causes vignetting, so I can't really use low powers to get wide fields of view. You also have to worry about focussing. There isn't enough travel for me to use my 5" refractor without using a barlow, which, of course, also increases the magnification. All is fine when I use my 5" Maksutov, but its focal ratio results in an even higher magnification and narrower field of view. So, under fairly light-polluted skies, that scope is too small to observe faint variables, but too limited in field of view to observe brighter variables with comps that are usually farther away. I think there are some binoviewers available with larger prisms, but they are very pricey.