Comments about B + W B + W 52mm Wide Angle Circular Polarizer Multi Coated Thin Glass Filter:

I really wanted to love this filter - brass ring, German-made - I love old-world quality - but I was ultimately disappointed with this product for several reasons.

The MAIN problem I had was trying to clean the filter in the field.
On a recent trip to the canyons of Utah, the filter became unusable after I tried to clean it. My normal lens/filter cleaning procedure - which has worked successfully for me for 40 years on a variety of lenses and filters from various manufacturers - did NOT work on the B&W filter. The filter surface turned into a smeary mess which I was not able to remove until I could get to warm soapy water - not easily found in the deserts of Utah.

My second biggest complaint with the B&W filter is this: It's hard to rotate.
Polarizers rotate in their mounting ring so the photographer can adjust the desired degree of polarization for a particular shot. This filter is slim (thin), and B&W has put serrations on the front of the rotating part for a better grip. But because there was so much internal resistance, the serrations cut into my finger tips like a circular hacksaw blade. I'm all for tight tolerances, but this is ridiculous! I've owned several other brands of polarizing filters and they were all much easier to use than this one from B&W.

Another issue was with the lens cap that comes with the filter. It doesn't fit tight enough for me to trust it to stay on the filter in my backpack. I didn't want the unprotected face of an expensive filter rubbing against other items in my backpack, so I felt it was necessary to remove the filter before putting the camera in my backpack, even when there was a good chance that the filter would be needed for my next shot.

Then there is the plastic box it comes in - which I found to be irritating in the extreme.
For one thing, it's much bigger than it needs to be - 88 mm square for a 52 mm filter. The box hinges open, but there are no markings on the top to tell me which edge of the box opens - it's slow to look at all 4 edges to find the one that opens. And once you find the edge that opens, it's very difficult to open it. You have to dig one thumbnail into a certain spot while pulling up on the lid; not so bad once I figured it out, but until then it was frustrating. Some filters which cost 1/3 what I paid for this one come with storage cases which are far more elegant and convenient to use than this one.

I have no complaints with the results I got during the brief periods when the filter was clean enough to use, but considering the other issues, I cannot recommend this filter.