Note from Elliot:
I have to admit that I have never seen anyone set up such an elaborate test but it does prove a point.
I have not used protective filters in years. Most certainly not since the advent of digital photography, which did not require UV protection.
There are non UV protective filters and I have one for each of my lenses and only use them under extreme conditions.
Smoke,salt water spray, blowing sand like particles, volcanic ash (I have never encountered volcanic ash), New Years Eve parties where champaign might be spraying around.
I do however ALWAYS use LENS HOODS which I consider much better protection under conditions not referenced above. Not only are they necessary to find LIGHT from adversely effecting an image but they too protect agains dings and usually do not shatter.
Photographers often use UV filters for lens protection, but how much are they actually able to prevent your lens from getting damaged? Photographer Steve P