Re: suggestions for red light

Jar-Jar:


Jar-Jar Binks wrote:
[...]
Why bother when you can purchase a red LED light for less than $5. In the
long run it will save you many tens of dollars in batteries because a
regular flashlight requires about 100 times the power of an LED. Making your
own red light is very un-cost effective in the long run.



The simple fact is that by means of adapting the eyes to low light conditions which makes the interior of the eye more transparent one can see far more objects and fainter objects than one otherwise could if the eye is light adapted.

Facts are facts.

LEDs, even red ones, produce too much light at frequencies other than red. The light must be filtered to block the non-red frequencies.

The cones of the eye are sensitive to red light, and the surrounding rods are not. The cones can also become light adapted, even in red light. Its a good idea to keep all light out, or just red light at a minimum. That means more viewing time.

Ralph Hertle
.

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