Interesting experiment, Alan. I've not tried it but a little research backs you up! One source (University of Illinois Dept. of Physics) says " The blue-sensitive cones are the least numerous, and are also spread out away from the fovea. This is one reason why it is harder to get a sharp visual impression of something blue than something of other colors."
I find the sort of white light I use for fine work (5800K color temp) tiring over time and I've read that the blue end of the spectrum offers better resolution due to the shorter wavelength. In any event 5800K lights are "bluish" but contain elements of the whole color spectrum just like sunlight. For something other than "white light", you may be right that a mixture of blue and yellow light (green) actually works better. There's also possibility a psychological effect about "blueish" light (e.g. sunlight) that has nothing to do with the physiology of vision. We humans are conditioned to be alert when bathed in "sunlight". Specialists in sleep disorders often recommend shifting to redder and dimmer lights as we move toward bedtime. They claim it greatly increases our ability to drift off to sleep. I do know from personal experience that it's hard to see detail in red light, having sat in many aircraft cockpits with the red night vision lights on straining to read a legend on a chart! Same is true for the bridge of a ship rigged for night. Whatever the underlying causes, I do find blue light jarring, while redder light is softer and more relaxing. I operate to relax. I was waiting for a hard-core contester or DX-chaser to say he/she wants to be wide awake and "on edge", that's why he likes the blue light. That would make good sense, but no one did - so far ;-) Never hesitate to challenge me. A forum like this isn't about "being right". It's about open discussion and learning. Tnx! Ron AC7AC -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Wednesday, June 17, 2009 11:55 AM To: Elecraft Mailman Subject: [Elecraft] Blue Displays and Visual Acuity Hi I'm really hesitant about challenging such an accepted authority as AC7AC on any topic. But I think he is incorrect when he says "blue light provides the greatest visual acuity." A simple experiment (which I have seen performed) can confirm this. Project a graded black and white resolution pattern in white light. Cover the projection lens successively with red, green and blue colour-separation filters and see how many of the patterns the eye can resolve in each case. You will be amazed at how few can be counted through the blue filter when compared with the green or, to a lesser extent, the red. This characteristic of normal human vision is acknowledged in the design of RGB television systems where less bandwidth is allocated to the blue signal. If it's acuity you are looking for, green is your colour, not blue! 73 de Alan G4LWA ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
