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Message: <blockquote data-quote="BruceH" data-source="post: 3438118" data-attributes="member: 106398">R G N ...... I recently purchased an outgoing Vortex Diamondback 8X42 for a great price and noticed that same problem you described.  I ended up returning it mainly for that problem.  I also have a 10X42 Zeiss Terra and an 8X42 Terra and do not have a problem with crescent glare as experienced with the Diamondback. I just went out and tested this an noticed that if I raise the 10X42 about an eighth of an inch, then some glare does appear at the bottom of the view (but not near as noticeable in the Diamondback).  When I place the binocular for what is normal for me, there is no crescent glare.   I believe what you are seeing is reflected light at the edge of the exit pupil.  Hold the binocular about 10 inches from your face and look at the exit pupils.  You may see a small amount of reflected light circling the edges.  You should also see reflected areas of light away from the exit pupils.  Those that are away are not a problem because the light falls outside of your pupil when viewing.  The light along the edge of the exit pupil is also normally not an issue because it to will normally be outside of your pupil if the binocular is properly positioned.  However, if you have the binocular placed slightly higher than it should be, then the exit pupil edge will be in line with your pupil and you may see this light as the crescent glare that you reported.  It can also appear under dark conditions even if you have perfect placement because your pupils are dilated to a size larger than the diameter of the exit pupil of the binocular.  Most binoculars in the price range of the Terra will show some reflection along the edges.  Even some very expensive binoculars have similar glare issues.  Overall, I find the Terra to be very good in this area, especially considering the price.  The physical design of the Terra works for me and I naturally position it without getting glare.  I have to position it to what feels unnatural for me in order to see the glare you described.  People with different facial structure may have a different experience.   Here are some comparison photos from Allbinos.  First is the Terra 10X42 which is fairly dark.  The second photo is the Nikon Monarch 7 8X30 which is much more sensitive to glare.  <a href="http://www.allbinos.com/lornetki_test_image/1246_terra_odbl_ol.jpg" target="_blank">http://www.allbinos.com/lornetki_test_image/1246_terra_odbl_ol.jpg</a><a href="http://www.allbinos.com/lornetki_test_image/1130_nik_mon_odbl_ol.jpg" target="_blank">http://www.allbinos.com/lornetki_test_image/1130_nik_mon_odbl_ol.jpg</a>You mentioned that you tried different positions and still see the glare.  That makes me wonder if you may have a defective unit.  Can you compare it to another Terra?  A coating failure somewhere could increase the reflections so that the glare is much more noticeable (similar to my Diamondback experience).  As far as the baffling goes, be sure and use a dim light to inspect inside.  A bright will reflect off edges so that they appear to be bare.  Using a dim light, the ridges you mentioned appear grey.  A grey reflected color for the interior parts is common for many of the binoculars I have.  In regard to the 8X42 vs the 10X42:  The 8X42 will have easier eye placement because of the larger exit pupil diameter  (5.25mm vs 4.2mm).    You will not have to be as precise when placing the binocular to avoid the edge of the exit pupil from aligning in front of your pupil.  There are other binoculars in the price range that may do some functions better than the Terra, but the Terra does everything well for me and the sum of the parts make for a great package.  It is my favorite in this category.  Good luck in sorting it out.</blockquote>

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