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Calculating exit pupil with a binovue

Started by paul.knight, 06/16/2014 06:33PM
Posted 06/16/2014 06:33PM Opening Post
I have a Televue Binovue with the 2x corrector. I would like to calculate the exit pupil. Let's say for example that I have a f/5 scope and a 10mm eyepiece. So I would do 10/5=2mm exit pupil. But with a 2x corrector would I divide this again by 2 to yield a 1mm exit pupil?
Posted 06/17/2014 05:56AM #1
That sounds right to me.
Try measuring the exit pupils with a transparent ruler. Differences will be obvious.

Another exercise: hold up your favorite eyepiece and note the exit pupil. Attach a Barlow and see how smaller the exit pupil is.

Posted 06/17/2014 08:24AM #2
Hi Paul,
You are correct...