I purchased a 52mm B+W MC Kaesemann Circular Polarizer. I just got it in the mail today.
I found something a bit confusing. The box says Digital MRC F-Pro. There is a sticker on the box that reads 52 MRC KSM POL Circular. The writing on the filter ring itself reads "B+W 52 KSM C-Pol MRC". The filter ring is black in color (not silver like they advertise for the digital filters).
Is it possible that the box has nothing to do with the actual filter? I remember seeing the "digital" version on B&H but decided to go with this one instead. The digital/non-Kaesemann version was about $30.00 less than this one.
Did I receive the right filter? Is the box simply a standard box? Is there any other way to tell if my filter is truly a Kaesemann other the the "KSM" printed on the front of the lens ring?
If the filter says KSM on the edge of the black filter ring it is a Kaesemann filter. I just got one as well. The box only indicates Kaesemann on the plastic seal - not the box. The box itself only says MRC Nano and has the B+W hologram - it does not say Kaesemann or KSM. The filter comes in a plastic box with a white foam cutout for the filter.
The Käesemann/Oberaudorf Company specialized in scientific grade glass and filters. It was bought by Schneider-Kreuznach -founded in 1913- back in 1989. B+W (Biermann und Weber) was founded in Berlin in 1947.
The difference with other filters is in the "extremely strict and exacting specifications of the glass", "the polarizing foil materials" and in the bonding of them to the glass, "an advanced cementing technique that prevents delamination" in high humidity environments.
This filter "does not impair at all the image sharpness of high-quality photographic lenses, which is particularly important in high-resolution digital cameras and aspherical telephoto lenses" as those used for wildlife.
The MRC coatings are superb. No scratches after 10 years of use. Another nice touch is the black anodized brass ring.
The designations for these B+W filters are: XS-PRO KSM C POL MRC-NANO F-PRO KAESEMANN CIRC POL MRC and the slim versions for wide angle lenses.
Very close -if not at par- to this perfection level is the Nikon Circular Polarizer II, with glass cut from Schott type glass bars, polished and sanded to exacting specifications too.
I have both the Nikon and the B+W. Never felt the need to make a comparison series of shots.
I also had a Hoya Pro 1 that a friend lost for me out in the field. Darn good (the filter)
Tiffen made and continues to make extraordinary filters for cinema. They have won Oscars for them. However, for still photography they have a wide range of quality that is hard to discern.