ADC1 Diffusor Cover / UV Filter - Clear
This is one of two diffusors that simply snap onto the silver 5" reflectors that we have made for about 45 years. This version is the more clear diffusor that will lose only 1/3 of an f-stop as it slightly softens and diffuses the light going through it.
Some UV light is absorbed as well so the light is softer and warmer than when direct from the reflector.
This is called the clear diffusor because you can see through it better than the other version. It loses less light output but does not soften the light quite as much due to having less diffusion. It loses about 3 tenths of an f-stop compared to not using it at all. However, it also spreads the light a little bit more evenly over a slightly wider area.
This Diffusor Cover is the same as one that was included with most Flash Heads when new. They simply snap on to the front lip of the reflectors. Because the reflectors are hand spun, it is not unusual for some to fit tighter or loser than others.
As a natural by-product of the light going through the plastic, some of the UV (blue-ish) light is absorbed, so some people prefer this diffusor for the "warming" effect of reducing the UV end of the light spectrum. The color temperature shift is only about 100 degrees warmer on a color meter but many photographers claim that the effect is more noticeable than that.
I have often gotten a free smile by telling people that it was keeping my light fresh and I wouldn't dream of using stale light at their event. It's not a coffee can lid, but almost.