will color LEDs help to see better?

I have a 12 white LEDs lamp. if I remove 4 of the white LEDs & replace them by 2 red & 2 green LEDs, anyone can advice by adding these color LEDs will helps me see better in the woods @ night? TIA!

They won't help if the other white LEDs are still turned on, their light will just wash out any benefits from the red and green LEDs. If there's a multi-setting switch on that sucker which allows you to use only 2 LEDs then that's OK. Just remember that if you have 2 red, as soon as any other colour LED is turned on, the benefits are gone.

Red preserves night vision, green will increase contrast making dark shapes like blood trails easier to see in the woods...blue does this as well.

To help you see better in the woods, you first have to decide if you want to see farther, or if you want to see more around you (spot or flood), or a balance of both. In either case you want to use white or yellow light, coloured lights are for special tasks but generally reduce visibility if used under normal conditions because your vision is simplified to blue & black, red & black etc. Red is the only colour light that can be used in the woods which will allow you to switch it off and not be plunged into total darkness with fried night vision.

i donno, but here are sum thoughts.

green reflects more light off of green stuff.

red and cyan are slighly low in "white" leds which are high in yellow and blue. a green and a red might bring the total spectrum closer to reading white in a METER thing.
(whites arent white)

whites have phosphors, which increases the ammount of light for the ammount of power.

red and green take less Voltage to trigger, so they (especially red) might not directally replace whites, so those 2 colors might run HOTTER than a white, which could give you a bad TESTing, because they would use more power, depending on how they were controlling stuff in the light to begin with.

so if you do, you would need to control how you did so, or offset the balance of power /ubbthreads/images/graemlins/smile.gif

Thanks guys!

When I mixed red & green LED lights (without white), I got something like a pale-yellow. & somehow I think I see more constast with this configuration...

I tried to look around more info & found Foxfury's headlamp using blue & green to make a headlamp better for night use.
http://img296.echo.cx/img296/2088/ffheadlampwater6gd.jpg
or maybe it should be blue instead of red will helps more than just a pure white light headlamp?

My idea is simply wish to see more contrast in the woods than my current white-light LED headlamp (which gives me a "ghostly" vision).

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DIYLite said:When I mixed red & green LED lights (without white), I got something like a pale-yellow. & somehow I think I see more constast with this configuration...

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True monochrome yellow is seen by the red and green receptors (cones) of the eye.

So mixing monochrome red and green lights will give a result that seems like yellow to our eyes -

But a spectrometer reading will say different - as the latter "yellow" is really made up of green and red....

Seems a bit obvious once said this way - but I didn't get it until I actually did some ad-hoc experiments - which I posted a bit back (linked) -

LED Colors and Vision (pics)

Under certain circumstances colored LEDs may allow one to see better than white light, it also may depend on one's eyes too. For example at lower light levels I find I seem to read better with a yellow LED for normal black print on white paper - it could just be my eyes - but I think the yellow does not dazzle as much as white and in terms of color contrast black on yellow is one of the most visible - hence I think many of the caution/warning road/hazard signs are black on yellow.

But there is no single color that's going to do everything - much as I advocate yellow (at least for myself /ubbthreads/images/graemlins/grin.gif) it doesn't suit everything - like trying to see yellow lines on a map.....

To preserve true human scotopic night vision - red is the only color that will do it. However many including me find it hard to see detail well under lower levels of red light.

Green light will seem bright - because our eyes are most sensitive to green - so it would seem the most "efficient" for our eyes - but it seems to give the wrong color contrast for seeing well outdoors for me - just like using yellow one loses the shades in yellow color - think about green light out among greenery......

Blue-Green or cyan/turquoise seems to do better for me - again possibly because the eyes will be using both the blue and green receptors under that light.

Blue looks cool and again will be bright - but for me not in a good way - blue tends to dazzle and tends to have some UV components - very good reason why blue-blocking sunglasses are so popular - so why deliberately choose blue light to see by?

Why? personal choice/taste, what may suit one person may not another - physiology explanations aside......

As far as color rendering and all, here is one take on it.

Camera was set to sunlight for all shots, so that camera corrections would not bias the pictures:

The halogen shows a definite bias towards yellow-orange, the RGB combo on the CREE shows a fairly 'white' lite, while the XO-binned Lux is a bit blue-biased, and is a little 'cooler' than the CREE. Interesting to see how it turns out.

RGB has better rendition than the Luxeon. For some reason I feel that the white balance on the RGB is leaning towards red.

Might help for a better "apples to apples" comparison if the light sosurces were at similar angles - the luxeon seems to be markedly lower than the halogen and RGB LED.

The colors in person are exaggerated. A camera doesn't have the same spectral response as the human eye, and they have adjustments for cloudy, incandescent, fluorescent, sunny, etc...

Here is a a section of each for better comparison:

Hi DIY Lite

FoxFury takes advantage of the Photopic Curve and provides Photopic vision. Green LEDs help with depth perception and cut back on shadow. This helps with vision in the outdoor environment.

The Water version on your link uses white, green and blue LEDs. This is the most optimal color combination for illuminating surface water.

Our website is: www.FoxFury.com

UnknownVT & NewBie thanks for your very interesting info here! /ubbthreads/images/graemlins/happy14.gif
CREE RGB can really brings out the color contrast real nice, but I noticed "rainbow" shadow also (will make u dazzle?)
I guess if I wanna use RGB to create "white" light, maybe not so a good idea to include white LEDs in the formula? /ubbthreads/images/graemlins/icon3.gif

FoxFury, nice LED headlamp you have! Can that model works well in the woods?
I am not really technical enough to understand "Photopic Curve and provides Photopic vision" /ubbthreads/images/graemlins/thinking.gif

great pics newbie

Interesting. One of my VIP renders colors of folage at night better than some of my stark white led light. This VIP seems to be a warmer white. I prefer xenon/halogen for night walking in woods. Good contrast, and depth of field. I would like to see more led lights available with the newer "warmer whites".

Bill

Good, interesting information on this thread.

I'm very impressed with the crayon photos, great idea.

Thanks for posting

DIYLite

Sorry for being overly technical.

Our Outdoor Version (4 green and 20 white LEDs) will work rather well in looking at foliage. The white light gives distance vision while the green light helps with details (enhanced depth perception and shadow reduction).

Photopic vision means optimized vision for a given environment. Here is a link on the Photopic curve if you are interested: www.guidetohometheater.com/features/204eye/index1.html

Hope that helps

Here is the eye response chart which you can zoom in on.

DIYLite said:

I have a 12 white LEDs lamp. if I remove 4 of the white LEDs & replace them by 2 red & 2 green LEDs, anyone can advice by adding these color LEDs will helps me see better in the woods @ night? TIA!

Click to expand...

For optimal full spectrum white light, I would suggesting adding the following to the Ce:YAG phosphor white LED's:
660nm deep red
505nm blue-green
465-480nm cyan
and possibly 495nm turquoise and 420nm violet

The Phillips L-prize "enhanced spectrum" white LED bulb seems to incorporate 620-630nm red LED's.
630-640nm red is also widely available.

You are probably wondering about efficiencies of these other chips. A high power 620-630nm LED is about 30 lumens per Watt, while a high power RGB white LED is about 50 lumens per Watt. But even if producing a particular frequency was less efficient, it only takes a small quantity to fill in a spectrum deficiency from other more efficient LED's, thus giving a better full spectrum combined white light that still has a higher net efficiency than other non-LED light sources.

Just an important note, when buying particular frequency LED's, it is important to be sure it is the correct wavelength, because often different types of LED's with different wavelengths of light are marketed under the same color name. For example, you probably would want a 420nm violet rather than a 404nm violet. Most of the common "violet" LED's being sold are 404nm, but this shorter wavelength is just barely within the human eye's sensitivity, making it less bright. And 404nm is commonly marketed as "cyan", even though the color is more accurately described as blue-green (since the frequency is more greenish than cyan).