# Cleaning a circular polarizing filter--how, when?



## notapro (Apr 28, 2013)

I have a B+W circular polarizer. On the inner surface there seem to be two flecks of something relfective, like pieces of glitter. They appear to be slighty larger than the size of a period seen at the end of any given sentence in a canonrumors post.

Should the filter be cleaned? If so, with what or by what method? Will dust or the "flecks" I see affect photographs? I suspect that they will not, or at least not any more than they would if they were on a lens surface, but would like to know more from those of you who have experience with this.

I am hesitant to clean the filter too agressively. This is what I have:

http://www.adorama.com/BW77CPLKS.html

Suggestions and thoughts?

Thanks


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## Mt Spokane Photography (Apr 28, 2013)

I clean mine the same way as any other glass. The polarizing grating is contained between two pieces of glass, so you are not going to hurt it as long as you don't slosh it with so much cleaner that it runs inside. 

First, blow any dust or particles away. Brush off specs if you can with a fine brush. Then wet a cleaning microfiber cloth and clean off any oily film. Do not scrub dirt that is still on the glass, gently wipe it away.


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## neuroanatomist (Apr 28, 2013)

I start with a blower, then a LensPen. If that doesn't do it, I use Zeiss lens cleaner (which is what I use at work to clean the multicoated elements of microscopes objectives, many of which cost far more than my 600 II) and a pec pad or lens paper.


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## notapro (Apr 28, 2013)

Thanks to Mt. Spokane and neuroanatomist for your suggestions.

I didn't have cleaning supplies (aside from a blower), so I went to a local store (Calumet Photographic), and they did exactly what you two have suggested (nice of them to do a cleaning job for me). I'll now be able to do the same.

I purchased a Lenspen, microfiber cloth, and a small bottle of "Ultra Clarity lens cleaner", which may be identical to Zeiss lens cleaner. (The cleaner is from Nanofilmtechnology, and the company's website mentions that their "Board of Directors is comprised of current and former senior executives for BFGoodrich, RPM, McFarland Dewey & Co., and **Zeiss** . . . .[emphasis added]".)

I feel a bit silly after seeing how easy it is to clean my filter, but I'm glad to be able to call upon the experience of others who know what they're doing to guide me.

Thanks again to you both!


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