Correct, when you look at coatings and see a particular color, that's the wavelength that the coating is "canceling" out. AR coatings have no color, here's a great article on the topic:
http://rick_oleson.tripod.com/index-166.html
I should also add that in my testing, I was trying to see the differences in tint with and without the coating (purple) and couldn't find anything discernible. This wasn't merely just observing it with my eyes but I videotaped it and then compared still frames. However, I believe a coating aimed at green wavelengths would have made a difference.
As an experiment, try shining the light around with the lens removed…see if it still gives that greenish cast you’re not liking. Curious to see if it makes any difference.
I just tried it. The AR lens of the BLF X6 does indeed cause the beam to look greener than without. Now I wonder why there haven't been flashlight AR lenses that look green instead of the typical blue/purple/pink (at least I haven't seen any). It might make for a more pleasant overall tint.
Edit: I'm curious if the stock non-AR lens changes the color at all. Unfortunately, I don't have one to test.
TL;DR
Single layer AR coatings target the middle of the visible light spectrum (green). This gives the highest light transmission throughout the visible light spectrum. But it causes slightly more transmission of the center target (green) then the rest. It also gives the lens a purple-ish reflection off the surface.
There isn’t anything they can do about it with single layer AR. Try an led tint that has less green to begin with. UCL lenses are advertised multilayer and supported by people saying it doesn’t have any green tint.
I'm guilty of not always reading everything before posting, so thanks for the clarification. I've gone over turboBB's link and think I kind of understand it now. I incorrectly assumed they could simply target the greenish blue or red part of the spectrum with a single-layer AR coating, but it appears that would negate the purpose of the coating in the first place, as it wouldn't affect enough of the visible part of the spectrum.
It seems like UCL is the way to go. I'll be picking up some UCLp's for my "better" builds and sticking with uncoated lenses for the rest. Even if the single-layer AR lenses do increase output, the shift toward green simply isn't worth it for me. It's actually the primary reason I haven't been using the BLF X6 much. An emitter swap does seem tempting, but I'm hesitant to mod the light after all the work that various members put into it.
locusto03, look at it like this… when you order food at a restaurant a chef has gone to a great deal of trouble to prepare your meal, correct? Then when you get it at the table, you add salt and pepper to taste, do you not? Modifying the X6 would be like adding salt to that dish, tweaking it to your taste.
The AR coating will not significantly increase output. These coatings are to decrease reflection and may increase or decrease transition, but only slightly. The only case where one is useful is to decrease ringyness in a light with otherwise a very clean beam. I think they are used to make the light resemble other optics rather than for any usefulness.
Depends on what you consider a “significant increase”. Decreasing reflection does increase light transmission. They will give you a few extra percent. Plus some bling! I love the extra clear view when admiring your led, especially with a nice smooth reflector. Also that nice purple reflection off the glass.
If you hold your light —lens facing toward a ceiling light —tilt back and forth till you see the light bulb/fixture reflect back on the lens—you’ll see not all coatings reflect the same color—most stock AR coatings reflect red the new UCL from Flashlightlens.com reflects blue and some Eagletacs don’t appear to add color at all— I have not done comparisons for tint reasons but I have done plenty of test to get rid of reflected outer rings in the beam profile—for example a C8 with clear glass has a band/ring around the outer spill that the UCL lens gets rid of
AR coating that many people saw,but didn't realize what they're looking at: gasoline(and similar stuff) on water creates that same AR effect,all those rainbow colors are created by different film thickness(note that both water and gasoline are colorless and transparent).
Kinda late to this…(wow back to 2015! lol) I just got my HaikeLite MT03 and the AR coating is defected (missing a small area)… and I did notice the output is weaker on some part when I had it on mid mode and close to the wall.
Since it’s already been necro’d, I’ll drop my 2cc:
The only torches I have that I experienced with and without AR coating are the Convoy S2 and C8. With the S2, I didn’t notice much of a difference (perhaps the AR lenses made the beam a bit more inclined towards magenta). In the C8, the AR lens diminished the “fried egg” tint shift by quite a bit, now it’s a very even yellowish white.
The thing about an AR coating is how well it’s applied. If you get a super cheap lens from FastTech or GearBest, Banggood, it’s not likely to be as good a coating as can be found elsewhere. The flashlightlens.com offerings are outstanding, optical glasses (as in prescription glasses) quality, comparable to camera lenses. In the case of the high grade AR, the difference is usually very noticeable. (once in a while a factory light has a great lens, my Klarus G35 had a super lens in it, but it’s not the norm)
The amount of light is even, but the area with no coating is dimmed and muggy on the wall (close up) turning the bazzle and relocate the defected area over oher LED shows the same thing. a small muggy spot on the wall (not sure the best word to use but muggy and dimmed is the best I can came up with)
“The term anti-reflective (AR) coating is deceiving. What it should be called is a ”transmission booster” or “light booster for a lens. What it does, in effect, is Increase Light Transmission through the lens. This is the single most important thing an AR coating does.”
