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Light throughput equation
I think everything about vignetting would remain the same in simple 8x32/10x40 binoculars if the same eyepiece and prism housings were combined with objective lenses of the same focal ratio, but I don't think there are very many examples of that in the real world. The 8x30 and 10x40 Habichts...- henry link
- Post #17
- Forum: Binoculars
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Light throughput equation
Exactly. The eye doesn't notice very gradual dimming and, of course sometimes there isn't any dimming in daylight conditions when a very large exit pupil is combined with a very small eye pupil. A shrunken 7mm exit pupil near the field edge may still have a cat's eye shape with a minor axis of...- henry link
- Post #9
- Forum: Binoculars
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Light throughput equation
There are some methods for making more precise images of off-axis vignetting in different binoculars. One is to shine a laser pointer into the objective lens with the laser output covered by a piece of frosted tape. The three photos below show (left photo) the shape of the on-axis exit pupil...- henry link
- Post #7
- Forum: Binoculars