Comments about B + W B + W 77mm Kaesemann Circular Polarizer Filter in Wide Angle Slim Mount, MRC Coated Glass.:

Color saturation and optics are very good with this filter but I found the rear surface to be very difficult to clean. The coating seems almost sticky and has a tendency to leave smear marks when cleaning

Comments about B + W B + W 77mm Kaesemann Circular Polarizer Filter in Wide Angle Slim Mount, MRC Coated Glass.:

This is a great filter. It's perfect on a wide angel lens because it doesn't cause vintaging. I have a canon 5D II and, 17-40mm lens and it works great not to cause vintaging.
The colors get very bright and saturated using this filter, and help getting read of or increasing reflections on water.
Also great for day landscape photography where all the colors get washed out otherwise.
Cons:
The only problem is, the suction cup was pretty loose, so i always had to put my hand on it make sure it doesn't fall, and finally I lost it.

Comments about B + W B + W 77mm Kaesemann Circular Polarizer Filter in Wide Angle Slim Mount, MRC Coated Glass.:

I shoot with a Canon 16-35mm F2.8 Mark I lens. I get noticeable vignetting with the regular profile version of this filter. If you go ultra wide angle, you need this filter to avoid the vignetting. Just one of those basic things.

Comments about B + W B + W 77mm Kaesemann Circular Polarizer Filter in Wide Angle Slim Mount, MRC Coated Glass.:

Does it's job....cuts glare. Only negative is price.

Comments about B + W B + W 77mm Kaesemann Circular Polarizer Filter in Wide Angle Slim Mount, MRC Coated Glass.:

Works great with my EF-S 10-22 mm lens. No additional vignetting at 10mm due to the slim design.

Comments about B + W B + W 77mm Kaesemann Circular Polarizer Filter in Wide Angle Slim Mount, MRC Coated Glass.:

Perfect in appearance with a blue hue this filter is very good at cutting glare and increasing color saturation. However unless the light is very strong it will cut shutter speed in half.

Lenspen glass cleaners don't remove stuck dust and only careful work with a clean lens cloth and cleaning fluid brands such as Giottos keep it oil free. It was only useful in environments with a lot of excess light or glare.