Roof Prisms Used in Binoculars (1 Viewer)

[WJC]

Some binocular models are presented as having a bigger prism than the standard, therefore a better image. Is this a marketing thing only?

Possibly! But the size of the field stop needs to also be increased and the over-all DESIGN needs to justify the increase. Too many observers will lay certain aspects of an image at the feet of ONE aspect of design and manufacture, ignoring all others that they don't know about.

The headbone ain't connected to the footbone!

 

[John A Roberts]

Bill recently posted about the passing of John Greivenkamp, see post #53 at: Dioptre Setting: Fallacy and Fact
John was Professor Emeritus at the University of Arizona's Wyant College of Optical Sciences. He was also the immediate past president of SPIE.
For details of John's life see: In Memoriam: John Greivenkamp

A 78 slide 6.2 MB presentation 'The History of Telescopes and Binoculars' by John and David Steed can be found at: https://wp.optics.arizona.edu/jgrei...017/05/Binoculars-and-Telescopes-OPTI-202.pdf

It provides an easily readable and well illustrated introduction to the subject, and the last part has details about the early use of prisms in binoculars.
It also addresses issues raised in some other recent threads.


John

 

[kimmik]

Would anyone know the rationale for reversing the order of schmidt pechan prisms?

ie I have noticed that Swaro puts the roof section on the eyepiece side, whereas Zeiss and Leica puts the roof section on the objective side. This might account for some of the swaro glare due to the roof edges being on the wrong side of the baffle, but maybe it also makes the image more sparkly? Is mirror then roof sharper than roof then mirror (due to the phase correction issue)?