B+W multicoated polarizer

[whitestone]

I recently purchased a B+W multicoated circular polarizer. When I

hold it at an angle under a bright light I see what appears to be a

textured surface (like the surface is just barely wrinkled). This is

only on the side that faces away from the lens. The other side

appears perfectly flat. I have another B+W multicoated filter (Red

29) that does not have the textured appearance. Anyone else notice

this on a polarizer?

[walterh]

What you see is the polariser filter foil. Its ok to see a hint of texture at e x t r e m e conditions - as long as it is not possible to notice this when looking through the filter or in the images. You might want to shoot a gray card out of focus stepped down almost completely. If you see any structure from the filter then you should return it.

[kevin conville]

I just looked at my copy of that filter and it looks perfectly smooth.

[peter_langfelder]

I also see the wrinkles, just barely under certain conditions. Haven't seen them in the photos yet :)

[Ed_Ingold]

The standard B+W polarizing filter consists of a plastic polarizing element sandwiched between two glass plates without cement. There may be a slight air gap and the foil may not be perfectly flat, but this has no photographic effect.

 

If you want a fully cemented polarizer, crack open the piggy bank and get the B+W Kaesemann polarizer.

[whitestone]

Here's a better description to see the effect: Hold the filter under a light source and look at the image of the light source on the surface of the filter, but focus your eyes on the surface of the filter (not the image of the light source), then you can see the wrinkled looking surface (particularly around the edge of the light source image reflection).

 

I sent an email to Schneider Optics Service Department asking about this and I got a personal call back! Talk about excellent customer service. I was told that this is expected behavior with a circular polarizer (not with a linear polarizer, though). It has something to do with light coming into the filter and bouncing back out, off the rear glass; the light passes twice through the polarizer and there is some interference going on. The effect occurs at angles between 15 and 45 degrees from perpendicular.