by JohnD » Sat Jul 04, 2020 10:27 am
Thank you, Ann, for those vidoes! I found the second from the lightning chasers especially 'exciting'!
But I'm sorry. On my screen I could not see a trace of green! Ann, as Colour Queen, can you support an alternative explanation, that of an effect in colour vision, an after-image? The observers, with wide, dark-adapted eyes, receive an intense red image, which saturates the red cone receptors in their retina. For a few moments, the imbalance in signalling to the brain causes a green after-image. The effect doesn't occur in light adapted eyes, watching a low intensity screen, because too little light reaches the retina to saturate the red receptors.
Try this experiment. Hold something very red under a desk lamp, so that it is intensely illuminated. Stare at it for half a minute, the close your eyes. I see a brief, green after-image.
And another Q, one for Chris maybe! Oxygen concentration at very high altitude. All I can find applies to flying height, deals with respiratory consequnces of altitude, and assumes that the relative concentration of oxygen and nitrogen remains constant. Why/how does diffusion mixing fail at the height of hundreds of kilometers, so that the concentration of oxygen rises?
John
Thank you, Ann, for those vidoes! I found the second from the lightning chasers especially 'exciting'!
But I'm sorry. On my screen I could not see a trace of green! Ann, as Colour Queen, can you support an alternative explanation, that of an effect in colour vision, an after-image? The observers, with wide, dark-adapted eyes, receive an intense red image, which saturates the red cone receptors in their retina. For a few moments, the imbalance in signalling to the brain causes a green after-image. The effect doesn't occur in light adapted eyes, watching a low intensity screen, because too little light reaches the retina to saturate the red receptors.
Try this experiment. Hold something very red under a desk lamp, so that it is intensely illuminated. Stare at it for half a minute, the close your eyes. I see a brief, green after-image.
And another Q, one for Chris maybe! Oxygen concentration at very high altitude. All I can find applies to flying height, deals with respiratory consequnces of altitude, and assumes that the relative concentration of oxygen and nitrogen remains constant. Why/how does diffusion mixing fail at the height of hundreds of kilometers, so that the concentration of oxygen rises?
John