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Binoviewers vs. binoscopes

Started by paul.knight, 02/16/2014 11:09AM
Posted 02/16/2014 11:09AM Opening Post
It was probably 5 years ago now that I had my first look through a binoviewer. I don't think I can ever go back to single-eye observing again.
That said, I am looking to put together a bino system that is as "grab and go" as possible. Should I opt for a telescope/binoviewer assembly (like a TV85 and binovue)? Or a binocular system like Vixen's BT81S-A?
Posted 05/11/2014 09:10AM #1
Sorry to take so long. This actually relates: I recently got a bunch of surgeries on my eyes and now have great vision in both...just like when I was a kid. So then back to the optometrist for new (very mild) eyeglasses. "You're better than 20/15 in either eye alone but improve to 20/10 when using both eyes. So (for nearly ALL of us) two eyes are better than one for TWO reasons! 1) Your L, R are different and used together blend their individual advantages. 2) TRUE binoculars (vs BinoViewers) combine the (uncorrelated) "seeing" from both eyes. Your brain is smartly filters the uncorrelated noise and you literally see more. And of course with double the photons! Physiologically and psychologically the stars "feel" more real and definitely clearer, brighter and more contrasty. VERY simple test affirming this: Just look at the stars naked eye with left only, right only and both. Unless one eye is terrible --- both is by far the best. P.S. I have many binox from Zeiss true pocket 10x25s to the giant JMI RB16s (takes a trailer...not a pocket). Tom Dey

29-inch Dob in a dome
36-inch upgrade soon
LUNT 80/80 solar scope
FLI 6803 cam
APM 100mm APO Binos
JMI RB-16 Night Vision Binos
Zeiss 20x60 IS binos
Posted 05/13/2014 10:39AM #2
For "grab and go" something like a TV85 + bino will be a smaller and lighter package.

If you like to view at high power for planets and moon, the TV85, which has an APO (apochromatic) lens, will be sharper. On the other hand, if you plan to do a lot of low-power viewing, the bino-scope (Vixen BT81) will give brighter images (it collects about twice as much total light vs. TV85). So it depends a bit on what you like to look at.

Another difference is that the binoviewer can be used with a star diagonal, and hence give right-angle viewing. This will make viewing at the zenith easier. Many bino-scopes (like the Vixen) give 45 degree viewing, so looking overhead is a bit awkward without some specialize mounting.