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reiner
November 4th, 2012, 03:36 PM
Having worked for many years as a researcher on the molecular basis of vision, I put together some aspects of vision, dark adaptation, and the differences between rod and cone vision and how it affects our deep sky observing on a new webpage

Interested? Read on here

http://www.reinervogel.net/vision/vision1_e.html

Marko
November 4th, 2012, 04:59 PM
Hello Reiner,
Have read the whole thing although I suspect my retention is a bit low on the in depth material. :confused: With some additional browse time on your site the filter page was found which aligns well with information seen elsewhere but was found to be presented in a clear and informative way. Well done and thank you so much for this great source of information.

davidem27
November 8th, 2012, 03:27 PM
I don't agree with you in anything! Ehehe...

Obviously it's an hard-reading piece, but really professional and it does tell something more than usual aknowledgements of night vision. Really thanks for sharing, Reiner!

Light OT, but concerning the night vision:

Tonight, after an observing session and once the Moon risen, I spent some moments on our beauty sky polluter to watch Rimae and Craters when the mirror was well cooled down in previous 4hrs of observation.
I saw the Moon for 10 min with right eye, my favourite.

Guess...
when I left out my eye from eyepiece the right pupil was blind.
My dark adaption of left eye was preserved from the bright Moon.

And so, just for fun, I experimented the difference in the observing place (during night sky) between dark-adapted eye and none by closing and opening eyes alternatively.

It seemed like a +3 stops of camera shot! :shocked: And, with the left eye, I could see things impossible to catch with the right one.

Okay, I'm feeling like "discovering the warm water", but...it was funny to check what we discussed in the past in the night sky ;)

Thanks for reading

Tetenterre
November 29th, 2012, 12:58 PM
Very succinctly put; thank you!

shneor
December 2nd, 2012, 08:39 PM
Hi Reiner,
Thank you for a detailed and enlightening description of the physical, chemical and biological vision process. I'm a bit surprised that you did not address the visual processing that takes place in the visual cortex (for example, one photon is interpreted as noise, two are information). I believe Dr. Larry Palmer at the University of Pennsylvania has done significant research in this area (http://www.med.upenn.edu/apps/faculty/index.php/g275/p11200). I don't pretend to understand it all, but you might.

Clears,

reiner
December 3rd, 2012, 02:59 PM
First thanks to all of you for the feedback.

Sure, the text is not exactly simple. But dark adaptation isn't that simple either :-) And there are quite some misconceptions about it.

Shneor: You are right, the biochemical aspects in the retina are only one side of all. There is more to it if it comes to the brain. But while I do know quite a bit about the biochemistry of vision in the retina, I am completely ignorant of the signal processing in the brain, so I rather leave that to somebody who knows more about it.