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Message: <blockquote data-quote="looksharp65" data-source="post: 3643413" data-attributes="member: 83771">Thank you Omid :t:Again, I'd like to stress that the power of a prism placed outside of the objectives will be multiplied with the magnification. Hence, a 0,5 prism diopter lens will require 5 diopters of eyeball convergence when used at infinity.At the same time, the image shift/increase of FOV will be a mere five meters per 1000 m FOV.On the ocular side, prism powers must be significantly higher to even be detected - to regain eyeball parallelity they must match the magnified anterior prism power.I disagree with you regarding the usefulness of a decreased medial compound FOV. If we're dealing with a reasonably wide-angle 65 degree AFOV, every part of the FOV will consist of true binocular vision. More than that, the "wide AFOV" will still cut away large parts of the human binocular field of view. Diverging FsOV will further restrict the (already) restricted compound FOV.And it does not stop there, unfortunately.When using the naked eyes, the human binocular field of view will follow with the version movements (up, down, left and right and combined vectors allowing oblique gaze directions), albeit with some restrictions caused by the nose and the eyebrows.At best, binoculars allow the eyes to roam the FOV, maintaining true binocular vision all the way to the field stops. There are undeniably lots of binoculars that will cause blackouts or kidney-beaning even with moderate version movements, but that's another problem.With a further restricted compound FOV, it requires a more active physical directing of the binoculars since the available eye roaming area within the FOV will be clearly more restricted.Regards,Lars</blockquote>

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