tag:blogger.com,1999:blog-34480619.post7893250211980299151..comments2024-03-11T13:47:03.621-05:00Comments on Physics and Physicists: Seeing Is Over-Rated, Part IIZapperZhttp://www.blogger.com/profile/15861398273820851809noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-34480619.post-48311200280282442002012-07-23T13:17:49.177-05:002012-07-23T13:17:49.177-05:00Before we disparage the poor human eye too much, h...Before we disparage the poor human eye too much, here is one area where "seeing" with the eye is not over-rated: dynamic range. Due to the logarithmic response, the human eye is capable of processing scenes over a range of 13-14 magnitudes of brightness. This is far superior to any CCD device in existence today. This is why high-dynamic range photography using even the best digital SLR's requires "stitching" together multiple exposures - one for the shadows, one for midtones, and yet another for highlights. The eye+brain does this instantly and automatically.Nonehttps://www.blogger.com/profile/14332398446544751306noreply@blogger.comtag:blogger.com,1999:blog-34480619.post-45739827720010503332012-07-22T15:18:58.527-05:002012-07-22T15:18:58.527-05:00As much as I would like single-photon sensitive, f...As much as I would like single-photon sensitive, femtosecond rise-time and a broader sensitivity bandwidth, I think the eye must at least be more energy efficient. The eye is also very pixel-dense!<br /><br />The human body, on about 2000 kcal per day, requires about 100 W. I couldn't find anything on the specific power requirements of an eye, but some single-photon detectors (Si APDs from Thorlabs) require about 9 W. I would be very surprised if the eyes account for 10% of the body's power consumption!<br /><br />To be completely fair, a lot of CCDs can run through USB and so probably have about 0.5-1 W of power requirement. They usually would not be faster than an eye if they had the same "pixel density" (see http://www.clarkvision.com/imagedetail/eye-resolution.html ) but would have much better QE. I still don't think my eyes require 0.5 W each.<br /><br />Although the number of "pixels" of the eye is unrivalled, it does not have much of an angular resolution...LGWhttps://www.blogger.com/profile/02374809820366400974noreply@blogger.com