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Message: <blockquote data-quote="denco@comcast.n" data-source="post: 3642765" data-attributes="member: 25300">I have never seen transmission's that low on the SE. I would trust Allbino's before I would trust those. Generally a porro will have better transmission better than any roof. Roofs don't have as wide of a fully illuminated view either. This is from Prof Edz over at Cloudy Nights."Transmission tests for comparative groups of roofs/porros in 10x42 and 8x40/42. Porros almost always show higher transmission than roofs. 618 Nikon SE 10x42porro 574 Nikon Monarch ATB10x42 rp 491 Pentax DCFHRII 10x42 rp ----Zen Ray Summit 10x42 rp 538 Celestron Regal 10x42 rp 579 Celestron Regal 8x42 rp 560 Bushnell Legend 8x42 rp 660 Garrett DCF 8x42 ApoRoof 750 Fujinon BFL 8x42 porro 630 Swift Ultralite 8x42 porro 770 Pentax PCF WP II 8x40 porro 880 Nikon Action Ex 8x40 porro The perception of higher transmission can be swayed by the illumination of the view. Very few roofs have as wide a fully illuminated view as do porros. With only one exception at 30%, most of the roofs listed above have only 10% to 15% of the view fully illuminated, then they drop off gradually to 50% illumination at the field edge. Many of the porros have 20% to 35% of the fov fully illuminated with a few reaching as high as 50%, before dropping off gradually to the edge. While this is by no means an exhaust sampling, of the comparable roofs and porros that I've measured, porros generally have not only higher transmission, but also better illumination. "edz<a href="https://www.cloudynights.com/topic/227610-some-roofs-transmit-just-as-much-light-a-porros/" target="_blank">https://www.cloudynights.com/topic/227610-some-roofs-transmit-just-as-much-light-a-porros/</a></blockquote>

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