Kinopless wrote:
Gotta disagree with the cheap filters being OK in good light. I've recently run a few tests for a friend who continually got un-sharp images from a 150-500 Sigma even in bright front-lit conditions.. Removing the filter made a real difference in sharpness. The filter was a $25 cheapie that the dealer threw in as a deal sweetener when buying the lens. A top class $120 Hoya has fixed the problem.
Kinopless, that will make Jerrys' tests, that much more meaningful and interesting.