I've been using for quite some time filter from Hoya and had previously never had problems with it. About a year ago I bought this filter at Dixons and him been used very rarely. The filter had but after some time a significant smear layer and could no longer be detached from the lens itself! After several failed Tips from the Internet, I put it in the freezer and the problem was solved. Then I tried the lubricant with a normal cleaning cloth rid, but I did not succeed. I I bought a cleaning kit and cleaned the filter with disposable towels and a drop of cleaning fluid. The lubrication could not be removed (now at the edge of the filter) and there are also scratches on it -.- I last out of desperation used a cleaning liquid for monitors. The grease has become a little less. Whether the cleaning fluid has the filter is damaged, but I do not know. Some time ago I bought me a polarizing filter from B & W and used this since quite often. Smeared this? No. Scratched this? No. It can be difficult to resolve by the objective? No. This is why I'm going to only buy filter from B & W. Even my cheap filter Tiffen, Cokin and Izumar are still free of scratches.
This time, there is unfortunately no recommendation to buy, what I find very sad.
