soft cloth and windex
same way you clean glasses or camera lenses
that aluminum coating is VERY fragile and thin, usually
wle
With the Chinese reflectors, you cannot touch them with any kind of cloth without damaging them, or use “first contact” solution because it is acetone based. The best you can do is rinse with soap and water, or purosol, followed by an air blast. There is no reason to go beyond a rinse + blast anyway because you cannot repair a damaged reflector by cleaning it, and any embedded particles are best left embedded, you aren’t going to improve on the situation.
It may be possible to physically touch the reflector surface without damaging it with certain techniques, such as soap + finger, with a very light touch / tap, or something along these lines, but you run a risk, and there is likely no need.
Electroformed reflectors with Si02 overcoat can be touched with a lens grade cleaning cloth without damaging them, and first contact solution can be used. These are a different grade of product than your average flashlight reflector.
A stubborn dust particle (or other imperfections) can usually be nudged with a split toothpick and removed with compressed air.
in the meantime, I cleaned the reflectors with Vinile Record antistatic liquid and hot air with good results.
I like to use silicone tape, it's a soft, transparent, solid rubber-like material that sticks to almost anything. It does not interact at all with the reflector (won't stick, scratch, or leave residue even if you press it hard against the reflector), but will stick to and remove any dust on it.
I understand why it does not scratch (very soft) or leave residue (completely homogeneous solid substance that does not break off easily), but don't understand why it doesn't stick to the reflector, not even a little bit. It's magic to me, but does make silicone tape the best reflector cleaner I've ever come across.
The last reflector I got from KD didn’t have any fingerprints or much dust on it, but appeared to have tiny dead insects. Weird!
I tried soaking it in water with dishwashing detergent, swishing it around, rinsing it under the faucet, putting it in distilled water, and then drying it with compressed air (from my air compressor). That made an improvement, but the insects remained.
So I took a cotton swab, dipped it in the dishwashing detergent water, put some dishwashing detergent on it, and gently rubbed it on the reflector. It was hard to hold the reflector since it was so slippery from the dishwashing detergent. Did the same again with rinsing and drying and it made a big improvement. Thankfully there were no scratches.
I repeated this several more times. There was 1 insect spot that eventually didn’t get any better, so it was time to stop. The reflector turned out great!
