View Full Version : Linear Polarizers

01-12-2006, 08:28 AM
Does a linear polarizer work on the DS when using manual focus? I know it won't work in AF mode, but my plan is to use it with manual focus. I have read conflicting reports of the effects of using linear polarizers on digital cameras instead of circular ones. Is it true that a linear polarizer can damage the AF mechanism of the camera? I'm only concerned in case I accidentally have my switch flipped to AF. How about light metering and overall functionality?

01-12-2006, 08:33 AM
I do not think a linear pol. filter can damage anything. It is not the sensor that has a problem with linear polarizers, but the AF method used. The AF can not determine focus when all polarized light is removed. A circular polirizer lets light with different directions through, allowing the AF to "see". Same goes with film SLR's.
So, you can use a linear polarizer on your Pentax. Just not with AF, as you already noted.

01-12-2006, 09:15 AM
I've used a polarising filter with 35mm in the past & tried a couple of shots to see how it faired using digital.

I didn't notice any problems with focusing but didn't see too much of an effect on the landscapes where I'd hoped to darken down the sky and enhance the clouds.

I personally find it better to post process in PhotoShop & adjust the Shadow & Highlights.