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Polarizer color shift

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Bob Mark
Polarizer color shift
on Sep 17, 2009 at 4:14:33 pm

While using a polarizer I have noticed a very big color shift when rotating the filter. I had to white balance again after setting the desired position of the filter. It's probably the rolling shutter.


Bob


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Felix Halter
Re: Polarizer color shift
on Sep 18, 2009 at 4:53:14 am

Same thing here! Some pictures were great and then turned very green while turning the polarizer. I guess we have to get used to white balance again after turning the filter.


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Bill Ravens
Re: Polarizer color shift
on Sep 18, 2009 at 12:07:46 pm

No. This isn't the rolling shutter. Funny how people can ascribe all manner of ills to a "rolling shutter", evil invention that it is. Chances are, the color shift phenomenon experienced with a polarizer, is due to dichroic filters used on the mirror system within the lens. Dichroics uses selective polarization to seperate out various wavelengths of light, either for metering or for capture by the 3 different (RGB) color sensors.



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Tim Kolb
Re: Polarizer color shift
on Sep 18, 2009 at 5:39:51 pm

[Bill Ravens] "Dichroics uses selective polarization to seperate out various wavelengths of light, either for metering or for capture by the 3 different (RGB) color sensors."

This would be the reason behind what is called a "circular" polarizer.


You might get less of a shift (though you will still have a shift) with a circular polarizer.

(and yes, I know they're all round...)




TimK,
Director, Consultant
Kolb Productions,


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Clint Fleckenstein
Re: Polarizer color shift
on Sep 18, 2009 at 1:56:33 pm

What do you think a polarizer does? Of course it's going to cause a color shift. That's why we photographers love it for outdoor stuff, since it blocks scattered light and makes for better color (deep blue skies, for example). I spent all day yesterday outside doing time lapses with a DSLR and EX3, and I put a polarizer on each one to clean up the shot and filter out all the bouncing blue-green light.

What do you think a rolling shutter does, by the way? Blaming the color shift on "rolling shutter" seems like blaming it for leaving the lens cap on.

Cf


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Bob Mark
Re: Polarizer color shift
on Sep 18, 2009 at 2:31:01 pm

I saw others discussing this on camera forums and thought I'd try it. I've never had this issue with my other cameras.

Bob


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Derek Reich
Re: Polarizer color shift
on Sep 20, 2009 at 1:27:11 pm

You cannot use a linear polarizer on the EX. It's that simple.... the result is the color shift you experienced while rotating the filter.

A circular polarizer will work just fine, and will not have the hue shifts at all. You do have to make sure the circular polarizer has the correct side facing outward however. (not a problem with a screw-in obviously, but with a 4x4 or 4x5.65 there should be an indication which side faces out)

problem solved.


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