Wow, I posted this question last week and got gang ignored, so I'll try again. I've got a pair of 83mm f6 achromats that just beg to be made into binos. Is there a rule of thumb or a formula for the spacing between the objective tubes? I'm thinking of using two 45 diagonals per tube for Ep holders. Is there abetter way? Is there a "don't ever try that" type of problem? Thanks, Randy
binocular question
Started by wayszl, 09/13/2002 10:05PM
Posted 09/13/2002 10:05PM
Opening Post
Posted 09/13/2002 10:49PM
#1
Randy,
Your question was forwarded to me by Herb York. In a short answer, it's not that simple as placing a pair of 45 degree diagonals together. You won't wind up with a left for left, right for right image. Your 83mm F/6 achromats need 2" focusers to avoid vignetting. There is no other way of merging the images without providing for IPD, Axial, Alt & Azimuth adjustments. If you are missing anyone of these adjustments, you cannot merge the images. Unfortunately it's very expensive to do just 83mm objectives. Most of my customers opt for 125mm objectives to justify the cost of the EMS backs I sell. If you want to see a pair of sucessfully completed Megrez 80mm Binoscope, goto
http://www.cloudynights.com
and check under big binoculars for an article by Derek Wong.
Joe Castoro
Your question was forwarded to me by Herb York. In a short answer, it's not that simple as placing a pair of 45 degree diagonals together. You won't wind up with a left for left, right for right image. Your 83mm F/6 achromats need 2" focusers to avoid vignetting. There is no other way of merging the images without providing for IPD, Axial, Alt & Azimuth adjustments. If you are missing anyone of these adjustments, you cannot merge the images. Unfortunately it's very expensive to do just 83mm objectives. Most of my customers opt for 125mm objectives to justify the cost of the EMS backs I sell. If you want to see a pair of sucessfully completed Megrez 80mm Binoscope, goto
http://www.cloudynights.com
and check under big binoculars for an article by Derek Wong.
Joe Castoro
Posted 09/14/2002 08:25PM
#2
Most people's eyes are in the range 55mm to 75mm
apart, so it will be difficult to make an 83mm
bino without some extensive plumbing. My advice
would be to find a cheap pair of old 7x35 or
7x50 binos, and fashion a way to replace the front
lenses with your 83mm ones. You'll avoid alot of
complicated plumbing work that way. The front lenses
on the binos will need to be more than 83mm
center-to-center, but you will find most old binos
meet this criteria. Have fun. - John B.
apart, so it will be difficult to make an 83mm
bino without some extensive plumbing. My advice
would be to find a cheap pair of old 7x35 or
7x50 binos, and fashion a way to replace the front
lenses with your 83mm ones. You'll avoid alot of
complicated plumbing work that way. The front lenses
on the binos will need to be more than 83mm
center-to-center, but you will find most old binos
meet this criteria. Have fun. - John B.
Funding Member
