Canon 16-40 zoom lens

[LeeO]

I want to get a polarizing filter for this lens. Two questions:

1. With a 10D I need a circular polarizing filter, right?

2. At it's widest angle (16mm), does anyone know if the filter will show at the edges of the frame and or picture?

Thanks

[Morden]

16-40? I don't think that Canon make such a lens. Do you perhaps mean the 17-40? Or the 16-35?

Anyway....

1. Sorry, I don't know anything about polarizers, but....

2. Due to the camera's sensor being considerably smaller than a 35mm film surface, the edges of what film would record are missing from the 10D's images (you get only a crop from the centre of the 35mm frame, hence the 10D's "1.6 X cropping factor"). It is very unlikely that you will see the filter in your photos, unless it is some sort of tube!

[Longwatcher]

Just to confirm a bit,
I have the 16-35 and the filters do not show up in the images at all on the D60 or 10D. I don't see how they could given the 1.6x crop factor.

I forgot the reason, but yes a circular polarizer is what is recommended for the 10D.

[Agent_Modder]

LeeO wrote:
I want to get a polarizing filter for this lens. Two questions:

1. With a 10D I need a circular polarizing filter, right?

2. At it's widest angle (16mm), does anyone know if the filter will show at the edges of the frame and or picture?

Thanks

1. Yes, circular is the one you need.
2. If you're talking about 17-40, my kenko PL mounted on top of a kenko UV won't show in the image.

[LeeO]

Thanks for the feedback, guys.

I could be wrong about the 16-40. I was writing the question from memory. It was tCanon's newest wide angle zoom (not fisheye) and the number I was most interested in was the widest angle (16mm). I could really care less about the telephoto part of that lens. It was expensive, though.......$1,349. Whew!!! That hurt.

[bluebomberx]

That would be the Canon EF 16-35 f/2.8 L at that price. It is not the newest. The Canon EF 17-40 f/4 L is the newest and is priced at $800.

[rdenney]

longwatcher wrote:
I forgot the reason, but yes a circular polarizer is what is recommended for the 10D

The reason is that Canon has always used beam splitters in the mirrors or focus screens for metering and for autofocus. The beam splitters behave like linear polarizers, separating orthogonal light waves. A linear polarizer may beautify the image, but it will also remove a lot of signal from the metering and autofocus systems. Not, of course, in any predictable way.

The circular polarizer uses a different technology and avoids the problem.

This has been a problem for me for 30 years. My Canon F-1 also requires a circular polarizer, but in those days they were three times the price of linear polarizers, or more.

By the way, I'd invest in a really good one for wide-angle use. The light is going through the filter at a shallow angle with an extreme wide angle lens, and that will greatly magnify any flaws in the filter. I'd stick with B+W multicoated filters, and probably get the wide-angle polarizer at that (which I believe uses thinner glass), or, at the very least, the Hoya MC filters. For the 77mm circular polarizer I just priced, the Hoya was actually more expensive than the B+W.

I keep reading reports of people losing image definition with their filters, and I've decided that I won't use lens protection filters therefore. A nice, stiff lens shade is protection enough, and adds to image quality rather than taking it away. But polarizers are worth the risk because of what they do to the colors in the scene. I just wouldn't skimp.

I have a 95mm linear polarizer for medium format. If you think the circular polarizers up to 82mm are expensive, you should price those really big ones!

Rick "who'd hate to muck up a kilobuck+ lens with a cheap filter" Denney

[LeeO]

Thanks guys. You were a big help.