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Message: <blockquote data-quote="brocknroller" data-source="post: 1750743" data-attributes="member: 665">I think the "feeling of clarity" that Kevin, John, and others describe in porros vs. roofs might be attributed to the greater 3-D effect in porros. Now that phase coatings have been perfected (or at least advanced) on roof prisms, which had been roofs' chief liability, given a porro and a roof of comparable optical quality (glass, AR coatings, etc.) and configuration, the only significant difference between the two designs is the greater offset of EPs vis-à-vis objectives in porros, which results in an enhanced 3-D effect. When I look through roofs, especially midsized and compact roofs, the views look compressed and unnatural, because the image seems almost two dimensional. I think the images in roofs can be confusing to the brain, because of this compression. For example, I have a harder time finding birds that easily blend in with the background with the 8x32 LX compared with the 8x32 SE, and those two bins have the same configuration, are made by the same manufacturer, and in the case of my newer SE and older LX, were made around the same time (2002). The perception of 3-D doesn't match what I see naked eye in roofs (though less so with full sized roofs). When I look through porros, the views look much closer to what I see naked eye. The 3-D effect in porros enhances the images, which I think is what people are describing as "clarity". Porros' enhanced ability to separate foreground from background allows the user to see his target more clearly and provides a more natural view of the environment. What led me to this conclusion was comparing the LX vs. SE, with two eyes and then with one eye. When I looked through the SE with one eye, the views looked similar to what I saw through the LX with both eyes. Of course, the stereopsis from using two eyes with the LX did enhance the views, not only the depth perception but enhanced contrast, but there was not nearly as much 3-D effect as when I looked through the SE at the same landscape with two eyes. Take a roof and a porro of the same configuration and of similar quality and you will probably see the same differences I did. I say "probably" because visual perception varies from individual to individual. Some people have greater ability to perceive 3-D effect, "globe effect," pincushion, chromatic aberration, etc., but there's a fairly good consensus on the enhanced 3-D effect in porros. The question is whether or not this is the factor that contributes to their greater "feeling of clarity". For me, it is. Perhaps our resident visual psychophysicist has some objective data on this matter.</blockquote>

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