Can somebody educate me on reflector-making technology - aluminum vs. composite (i.e. plastic, but it sounds bad)? Are there different ways of coating the reflecting surface?
Also, the front lenses are sometimes coated with anti-reflective film. I imagine to minimise light losses between the LED lumens and the OTF lumens, but how effective is it? Have anyone tried to measure it?
Bump. I guess my question is: is there a rational reason to avoid plastic reflectors?
Edit :
Sorry, i made a mistake !
One of my first real flashlights, the Romisen RC-29, has a white plastic reflector.
I don’t know if having a plastic reflector is good or bad, but the reflector should be reflective, in my opinion, and the reflector for the RC-29 is not very reflective.
I guess if a flashlight is outputting a ton of lumens (and heat), perhaps a plastic reflector could melt?
Otherwise, if a plastic reflector is reflective, I think that it’s probably a decent solution. 
I knew I’ve read that highly reflective coatings, certainly on smooth reflectors, are often applied by means of vapor deposition, so I did a quick google search and found an interesting article, that also mentions AR coating:
Also an example of a company who does reflective coatings through vacuum vaporizing:
A more in-dept article:
Some interesting information on vacuum vaporizing in general:
I did amateur-level test on Wurkkos TS30S which didn’t come with anti-reflective lens, replacing stock lens with an AR lens. The part that’s relevant to your question is underlined below. So long ago I don’t remember details but do remember the gain is unequivocal. (I tend to repeat a test many times before arriving at a conclusion.)
Pardon me if you already know, but I should add that although the main reason “normal” people use AR lenses is for increased transmission, for hobbyists, especially those tint-snob people , there is a second reason. And the reason is that the type/color of this AR coat affects the Duv and could make the beam color more rosy, less green.
Put the lens under ceiling light and look at the reflection of the light bulb in the lens. It’s either no change (no AR lens), or has either green or purple reflection. The green-reflection is what you want if you like to lower Duv (about 15-20 points) and make the beam more rosy. When I order lights from Convoy I would PM Simon to ask for the green AR lens, because Convoy could switch from green to purple in the middle of production, as is what happened with my M21E. Hope this helps.
