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Message: <blockquote data-quote="edz" data-source="post: 1557630" data-attributes="member: 44073">No doubt the light is coming from above, however, it was my suspicion that it is reflecting off of the retaining ring.  I may have proved that suspicion incorrect this morning.  I added black flocked felt (green sticky fetl blackened with marker) to the retaining ring, and it didn't change anything.Henry mentioned earlier, you can stand behind the binocular and look at the exit pupil and see the very bright reflection arc across the bottom of the exit pupil.  The fact that the flocking seemed to be no help indicates to me it is stray light reflecting from some internal surface, or perhaps even more than one surface.Some people have suggested a correlation with wider angle eyepieces.  I don't think so.  Stray light is controlled with proper baffles.  Baffles are always in front of the focal point.  Baffle diameters can be cut too large and prove ineffective, or can be cut too small and reduce apertue, but baffles have no effect on the field of view.  The baffle in the ED2 is in the movable lens element.  When that element is all the way forward, at closest focus, that baffle diameter is actually slighly to small and is controlling the aperture.  At closest focus, the baffle cuts into the light cone and reduces the binocular to 40mm.  At infinity focus the baffle is further towards the rear, closer to the prism, and the light cone passes the baffle and hits the prism aperture.  Now, that is just in reference to the on-axis light cone.   At infinity focus the baffle is slightly too large and perhaps allows some stray light to pass.  There are more baffling requirements for off-axis light to prevent it from becoming stray light.It is not uncommon for baffles to be mis-sized.  Although not related, these are examples of baffles that are too small.  I've had an 8x40 that had a baffle so mis-sized that it cut the aperture to about 32mm.  I have here right now a 12x50 rp with a movable lens element in which the movable lens element, when  is all the way rearward, does not interfere, but when forward, the baffle reduces the aperture to about 46mm.edz</blockquote>

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