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Message: <blockquote data-quote="Kevin Purcell" data-source="post: 1290732" data-attributes="member: 68323">Sharp vision (foveal vision) is much narrower than you may think. See the graph here.<a href="http://en.wikipedia.org/wiki/Fovea" target="_blank">http://en.wikipedia.org/wiki/Fovea</a>Your mind does a great job of integrating the small sharp patch of perhaps 6 degrees across at half acuity ... a tenth of the typical AFOV were talking about here (now that's a lack of edge sharpness <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /> ). Your eyes saccade around the scene to pick up the details which your brain uses to generate your visual perception.<a href="http://en.wikipedia.org/wiki/Vision_span" target="_blank">http://en.wikipedia.org/wiki/Vision_span</a><a href="http://en.wikipedia.org/wiki/Saccade" target="_blank">http://en.wikipedia.org/wiki/Saccade</a><a href="http://en.wikipedia.org/wiki/Visual_perception" target="_blank">http://en.wikipedia.org/wiki/Visual_perception</a>Surrounding the fovea is the macula which has cones at a lower density so provides lower resolution (as you can see from the curve I pointed to above). <a href="http://en.wikipedia.org/wiki/Macula" target="_blank">http://en.wikipedia.org/wiki/Macula</a>Surrounding that is mostly rods for monochrome vision wired to detect movement in the periphery of your visual field. These are the elements that see the bird moving so you can center the bins FOV on it.<a href="http://en.wikipedia.org/wiki/Visual_field" target="_blank">http://en.wikipedia.org/wiki/Visual_field</a><a href="http://en.wikipedia.org/wiki/Peripheral_vision" target="_blank">http://en.wikipedia.org/wiki/Peripheral_vision</a>See these other pages for more general info on human vision and acuity for a bit more background:<a href="http://en.wikipedia.org/wiki/Visual_acuity" target="_blank">http://en.wikipedia.org/wiki/Visual_acuity</a><a href="http://en.wikipedia.org/wiki/Optical_resolution#Ocular_resolution" target="_blank">http://en.wikipedia.org/wiki/Optical_resolution#Ocular_resolution</a>Understanding how the human visual system works enables you to see why bins have some of the trade offs we see (and why people don't notice some of the problems like edge sharpness or the lack of it).Apologies for the lack of direct Promaster content!</blockquote>

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