In my quest for the perfect circular polarizer for my Canon 100-400 lens I finally settled on the B+W 77mm XS-Pro Kaesemann High Transmission Circular Polarizer MRC-Nano Filter. Dang, that’s a mouthful but what does it all mean? For starters, Kaesemann is a precision glass company purchased by Schneider Optics of Germany in 1989. The high transmission designation refers to the ability of the glass to transmit light. This filter is advertised at 99.5% with a filter factor of 1 to 1.5 stops of light loss due to the darkened blue glass. The MRC feature is Multi-Resistant-Coating, which is a series of layers designed to prevent reflections and ghosting while the NANO designation refers to a hardened eighth layer that assists in keeping the filter clean. The B+W filter is constructed using a brass outer ring that provides an exceptionally smooth threading capability when affixing the filter to the lens. The rotating mechanism for turning the filter is stiff but very smooth. The construction of this filter is superb.
That’s all well and good of course, but does it work, that is the real question! Today looked like a perfect day to find that out as the sky is perfectly clear and the sun was beating down on the snow capped Sangre de Cristo at almost a perfect 90 degree angle this morning. Just looking at the mountains they appeared washed out and faded to the naked eye, perfect conditions for a polarizer.
So, I pulled into the overlook parking lot and shot one picture with no filter followed by another picture with the circular polarizer with the glass turned to maximum effect. I shot in raw as always, but applied no processing to these two images, as I didn’t want to pollute the results of the test with a bunch of Photoshop adjustments. Here they are, first the mountains with no filter and then with the filter:
As you can plainly see, the second image has significantly increased saturation and detail in the white highlights of the snow capped peaks with a much deeper blue in sky. The snow and trees just below the peaks are also much more visible in the polarized image.
I will also be trying the filter out over water when I find some! Not much water around here in this mountain desert, but sooner or later there will be a river or a lake in the sun where I will find the filter useful! All in all I would say I’m extremely happy with this purchase from B&H Photo Online and would highly recommend the filter to anyone using a DSLR camera.