An excellent follow up for this lens filter test would be to compare results using flash into the lens. The modelling lam used in the video has 150 watts and was placed less than a meter from the lens. It would also be worth comparing a new UV filter with a used UV filter, one with modest cleaning marks on it. However the difference shown in this video has reinforced my decision to avoid using filters. Situations when I would make an exception would be at the beach when windy, when photographing in hazardous environments like factories or even anywhere people are drinking. I wasn’t exaggerating when I stating I have had my 24-70 f2.8 at one hundred weddings and it is not scratched. If you always use a lens hood and be sure to clean your lens both gently and sparingly you can negate the need for filters. If I am wrong, if my test is flawed, leave a comment or request a new comparison.