The use of red light in darkrooms, went out many decades ago with the
introduction of pantographic film emulsions that were sensitive to all
colors.  Orthographic film as used in the early days of photography were
'blind' to red light, hence the use of red in the darkroom.  For over 50
years, darkroom 'safe lights' have been yellow-amber. 

Safe lights are used so we can see, but the color is chosen to make it a
color that the film doesn't see.  Its not necessarily best for our vision,
just best for the film or other light sensitive material.

I've heard that night lighting inside submarines is blue to protect the eyes
for those that are transitioning from inside to outside.

...bill  nr4c

-----Original Message-----
From: Ron D'Eau Claire [mailto:r...@cobi.biz] 
Sent: Monday, September 23, 2013 8:48 PM
To: elecraft@mailman.qth.net
Subject: Re: [Elecraft] KX3 Backlight color will remain amber

Also, human vision has the lowest acuity in the red region. That is, we see
less detail in red illumination. 

73, Ron AC7AC


______________________________________________________________
Elecraft mailing list
Home: http://mailman.qth.net/mailman/listinfo/elecraft
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Elecraft@mailman.qth.net

This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html

Reply via email to