polarizer filters film/ digital?

[Jimmy B]

Haveing just gotten the Canon1V, I was wondering if anyone has had some experience with the 2 different polarizers? I do have a circular one. I am not sure what my cokin is?
Thanks for any input, Jimmy B

[Greg McCary]

Haveing just gotten the Canon1V, I was wondering if anyone has had some experience with the 2 different polarizers? I do have a circular one. I am not sure what my cokin is?
Thanks for any input, Jimmy B

The Cokin version just fits into the Cokin holder like any other Cokin filter but it's not square it's round. You wouldn't gain anything with a Cokin version unless you were out shooting with grads and decided you wanted to pop in a polirizer.

[Chris350]

Linear vs. circular polarizers: Linear is the old style works with film and manual focus. As I understand, circular polarizers are recommended for use with modern digital and AF systems because of some way linearly polarized light affects/interferes with the function of the Auto Focus. There may be in interference with the filters on the digital sensor as well. I have used a linear polarizer on a Nikon DSLR and I'm fairly certain it worked alright.

[wfooshee]

Linear polarizers will confuse the TTL metering and AF sensors. The errors come from the fact that in modern cameras the reflex mirror will have a partially reflective zone, or indeed the reflex mirror may be entirely partially reflective. Polarized light reflects (or passes through) differently off partially reflective mirrors than it does fully reflective (or clear glass.)

Light through a linear polarizer will reflect from this mirror differently when the polarization is oriented one way instead of another, changing the amount of light which reaches the metering system. I've read that the difference might only be a stop either way, which with print film or digital isn't too big a deal, but with slide film could be disastrous.

The same reflectivity difference affects AF sensors, causing in "in-focus" results to be, well..... not.

A circular polarizer is a linear polarizer, with another layer of filter glass that circularizes the light passing through. This gives you the effect of a linear polarizer on your photographs while passing usable light through to the camera's sensor. The linear part, which the light passes through first, does the filtering job you expect of it, and then the second layer changes the light back to something the camera's optics and sensors can deal with.

Any auto-focus SLR should use a circular polarizer, and many manual-focus SLRs, depending on the metering system, would also require circular polarizers. Note that there is no distinction between film and digital. It's the AF and metering that determines the need for circular polarization over linear.

[Jimmy B]

Thank you all for the input and the explanation. Now that I have looked at the cokin i have a P164 circular polarizer filter. This filter will do well with the 1v body and film. I am looking forward to shooting the 1V.
Jimmy B.

[alexau]

Polarizers also help in reducing the haze in like the Grand canyon and Sedona... Brings out the colors in the rocks... Just try even a pair of polarized sunglasses to see the results. It cant really be done the same with Photoshop. You can take some out with desaturating the blue layer but polarizer works well in that situation too...

[sofa]

I've read that the difference might only be a stop either way, which with print film or digital isn't too big a deal, but with slide film could be disastrous.