Flashlights LEDs produce different colors by using various materials, which produce photons at different wavelengths. Those individual wavelengths appear as light of different colors. Red LEDs use the aluminum indium gallium phosphide (AlInGaP) material system. Blue, green and cyan LEDs use the indium gallium nitride (InGaN) system. Together, AlInGaP and InGaN cover almost the entire light spectrum, with a gap at green-yellow and yellow. One method of achieving a larger spectrum of colors is to mix different colors of LEDs in the same device.
Combining red, green, and blue LEDs in a single LED device, and controlling their relative intensities can produce millions of colors. Additionally, combining red, green, and blue in equal amounts produces white light.
Different lighting colors have different meaning, and look at what they are generally used for: White: great for all around, every day illumination. Red: ideal for camping, navigating the way in the dark, preferred by people who are trying to save their night vision. And red light is the universal signal for caution and safety. Green: suitable for hunting. Many hunters claim animals are not frightened off by green lights. Blue: great for tracking blood trails along the foliage, it can be used by hunters, police and crime scene investigators. And blue light can cut through fog, which is widely used for fog headlights. UV: it’s aids in authenticating money, driver’s licenses, and other documents by making the special watermarks fluoresce. UV light can also make blood and other bodily fluids easily visible. Stains left by mice, dogs, cats, and other animals will also fluoresce under the UV light…
Upon your demands, do you prefer flashlights with single white light or colorful lights? And how do you use them?
I only own these 3. Red is great for preserving night vision. I used to backpack with a guy who had really sensitive night vision. I guess his eyes dilated really wide open. So any amount of white light would mess him up. So I used the Bushnell or SF-A2 red LED light and let him take point. I kid you not he could spot things in the dark like an owl. There was one time a group of raccoons were just off trail as we approached a camp site, even with the red lighting I thought they were bushes!! They’re smart animals, probably waiting for people to enter the camp site to steal food.
The energizer hard case I used the UV light clipped to my waist, pointed down to the ground to highlight scorpions on the trail (they glow under UV). One of the trails I used to night hike, certain times of year had scorpion nests. They usually retreat into their nests, but still its good to spot them if you can.
All these lights broke, developed intermittent contacts that I could not repair. The SF-A2 still works, but the incan lamp blew out several years ago and I haven’t really cared to replace it. I never really used them for mall ninja tacticool stuff… body fluids, blood tracking, counterfeit ID or money…etc
There was another time I car-camped at a state park and an astronomy club had reserved a hill-top area of camp sites. This was a major operation mind you. Guys had trailer size telescopes, that were hooked up to servo motors, laptop computers huge batteries so they could track planets and stars across the sky. Enthusiasts were here from across the entire western united states. Anyways the park had a “red light only” camp rule for that hill top area. The astronomy club was super generous with their time too, but they got pissed quick if you messed up their night vision with anything other than red.
Fun fact… you know how colonial era pirates in TV, movies and Disneyland are always depicted with a patch over an eye? Everyone thinks its because they lost an eye in sword fight with peter pan or something… right? No its so they can keep one eye fully dilated for night vision when they go from one area of the ship to another at night. They switch the patch from one eye over to the other depending on the ambient lighting conditions.
I never figured they had artificial light strong enough to induce night blindness. Certainly not on deck. Bee’s wax and spermaceti oil were used for candles. Mythbusters did a segment on the eye patch myth, and found it plausible but without any historical fact. More likely they were used to protect a damaged or open eye socket. The side of a ship being hit by a canon ball would send thousands of wood splinters in all directions, not to mention musket ball gun fire. Often they would load canon with nails, musket balls, gravel, chain, or anything else they could find to knock down the enemy rigging and cause casualties. So, no surprise many wore eye patches.
Can’t imagine what it was like for sailors back in the 1700’s on board a ship for months or years at a time with no eye protection from the sun.
Yep… I have various small reflector, flood-type lights with warm 3-4K tints that go down into the ~2 Lumen range. I have no need for red to preserve my night vision.
