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Message: <blockquote data-quote="OPTIC_NUT" data-source="post: 3223253" data-attributes="member: 121951">Going through a pile of vintage binoculars to see which had 'veiling glare', I found two pair with very noticeable issues.  When I looked inside, the normal2nd stage of the baffle tunnel was not there.  The threads for tunnels were thereand I was able to find fitting parts in my parts pile, resulting in zero glare...and better contrast as well.I don't know if they were left out in manufacturing or in a prior cleaning, but that's a possibility when you see this issue.  "In my experience exterior hoods are only effective against this kind of glare if they are quite long. The geometry of the situation is pretty simple. The bright lens cell reflection that causes veiling glare occurs on the opposite side of the lens from the offending light source, so a hood has to be long enough to shadow the opposite side of the lens from the source. If the problematic light source is 30º off-axis then the length of the hood needs to be about 1.5 times the objective diameter, if the light source is 15º off-axis the length of the hood needs to be about 3 times longer than the objective diameter."---The assumption behind this geometry is that there is nothing at all between the objective and    the lit surfaces.   I don't think I have any binoculars with no baffle tunnel at all.   A short hood merely    minimizes the area the stray light splashes on.         When you shine a light in, surfaces appear to be in a line, but the effect of the lenses on what you see   hides the fact that they are not. For example, the front tunnel appears to be a straight tube, but it   in in fact a steep taper.   Proper design of all the diameters keeps the stray light from ever reaching   the eyepiece.  If you need a very long hood, you have no baffle tunnel at all.  There are binoculars   with too-short tunnels, so it's possible...</blockquote>

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