Another polarizer question

Since circular polarizers were developed, primarily, to acommadate lenses that turn when focusing. . . is there a special need for using circular vs. linear polarizers on the end of the lens for digital cameras?

Actually, circular polarizers were developed for cameras with TTL (Through The Lens) metering, nothing at all to do with rotating lenses.

You should use circular polarizers.

was at the car show the other day
and i was taking a photo of this car that had a piece of paper on the dash
when i adjusted my CP....

HTTP response: 404 | MIME changed to 'text/html' | Byte size: ZERO

The heck with the paper, or the ploarizer . . . I want the Impala! That's a gorgeous ('59?) hardtop!

yeah nice impala.

Mmm...'61 Impala. :drool:

I was thinking that it would be difficult to use a polarizing filter on a lens that rotated when focusing. Unless maybe you focused and then adjusted the filter, but I don't know. I have one I can use on my 50mm 1.8, but the end of that lens does not rotate.

It's got to be more than just the TTL metering, because we've been shooting with film that way with linears for years. I might bite on ETTL if that's the case. I'm not arguing with anyone, just curious.

thanks guys
yeah it was a beauty
so is a linear one that you dont have to rotate?

You have to rotate both types of filter. A linear polarizer is not suitable for TTL AF due to the way it effects the incoming light.

May I suggest you read this:
http://www.luminous-landscape.com/tutorial​s/polarizers.shtml

Or this:
http://w1.541.telia.co​m …rs_faq/filters.​html#polq2

Or even this:
http://www.outdoorphot​ographer.com …2001/july/polar​izing.html

Got it. Good links. However, correct me if I'm wrong, aren't linear polarizers what we have been using all along? At least up until the last couple of years.

I switched from a different camera brand to Canon in 1997. At that time, I discovered that my old linear polarizer didn't work right on Canon. Then I discovered that circular polarizers cost more than linear ones.

---Bob Gross---

linear polarizers affect autofocusing mainly, TTL to some effect as well, but AF is the main reason that we have to use circulars. Remember - the sensors in AF are checking the vertical and horizontal lines to focus (cross sensors at least, regular - only vertical lines)