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Message: <blockquote data-quote="Binastro" data-source="post: 3470611" data-attributes="member: 111403">Regarding resolution of holes.I punched 5.85mm or 0.23 inch holes in a foolscap white sheet of paper.At night with the paper against the window, dark outside. Kitchen illumination 6ft fluorescent tube.The furthest back I could get was 12.82 yards, Leica Disto rangefinder.Correcting for .22 holes this gives 12.25 yards.The holes were easily seen with my distance glasses, 20/16 vision rather poor room lighting for me, perhaps 4mm pupils. This was with either eye or both eyes.In fact I glimpsed them without glasses where my eyes are completely out of focus, and very poor resolution.Using binoculars I think it essential to tripod mount them or use current model Canon IS binoculars.The difference is glimpsing or seeing steadily.The improvement should be above 50%.I don't know what the standard conditions are meant to be, but the essentials are.Illumination.Contrast. (If this is poor then there is a drastic reduction in resolution).Background darkness and colour.Pupil size.Acuity.Steady image.I can't think of a suitable location here to place the holes at 100, 200 or 300 yards and view with binoculars.Looking at the full Moon, I could easily make out the brightening around the crater Tycho with unaided eyes and distance glasses, but only in the dull reflection in the double glazing which retains all the detail. The normal brightness Moon seen directly was too bright and washed out the image.P.S.For seeing  the small holes, the illumination should not be too bright or too dull, ideally variable neutral density filters should be used.Some British military binoculars had filters within. These were good, but fixed densities, not variable.The background to a white target should be black.If the background is light the holes might not be seen even close up.As well as tripod mounting the binocular, ones head should also be braced. For me this provides about 10% more resolution.For unaided eyes viewing with distance glasses on a bright day, a large neutral density filter can be tilted until it gives the optimum density.</blockquote>

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