Vignetting?

[Rhys]

I have a Tamron 17-35 and am thinking about getting:
1. UV multicoated filter to keep dust off the front element.
2. Polarizer

Now, there are two varieties of polarizer - slimline and normal. Which do I need? Also, would stacking the UV and the polarizer begin to vignette the images?

[George Riehm]

At 17mm f/2.8 adding filters will increase vignetting, but it may not be a problem, especially using thin-ring types.

Here is a pointer to the photozone lens test showing vignetting without a filter, mounted to an XT.

http://www.photozone.de/8Reviews/lenses/tamron_1735_284/index.htm

[noyjimi]

I have a Tamron 17-35 and am thinking about getting:
1. UV multicoated filter to keep dust off the front element.
2. Polarizer

Now, there are two varieties of polarizer - slimline and normal. Which do I need? Also, would stacking the UV and the polarizer begin to vignette the images?

Not a direct answer to your question, Rhys, since I've never used the 17-35, but on the Canon 17-55 (and 17-85), I've used a normal CPL with very minimal additional vignetting on top of what the naked lens already has at 17mm wide open - maybe since it's quite a bit to start with, on these ones, anyway.

If you do plan to use the same filter on an UWA lens, your better bet is the slim. You might end up having to use a dinky push-on cap instead of the regular one, though.

I imagine stacking would increase the light fall-off - I always take off the clear when I use the CPL.

[Rhys]

At the moment it's pouring down with rain. I went and bought some filters. I couldn't get the Schneider filters that I wanted nor the Kaseman nor the B+W. My cheapo Ritz only had Tiffin so I skipped on that and went elsewhere to get ProMaster. Heaven alone knows if they're any good. I'll test them when I'm in Cherokee at the weekend.

[coldrain]

Since the 17-35 is a full frame lens, there is no way a filter will add vignetting.

[Vich]

Since the 17-35 is a full frame lens, there is no way a filter will add vignetting.Even full framed lenses sometimes vignett on APC cameras. I do not speak from experience since I have never explored Ultra Wide, but wouldn't an extra filter not explicitly designed to avoid vignetting only add to the problem?

[coldrain]

No, the light fall off "vignetting" is very different from filter vignetting. Filter vignetting is the filter actually coming into view, blocking the corners for real. Since this is a full frame lens, no filter will block the corners like that. Also, the 17-35 is designed to allow for filters, that is why the lens casing is so wide around the glass... so even on a full frame camera you are still able to have a filter on it without it vignetting. Unless you use an unusually thick filter of course.

[Rhys]

Stacking 2 filters (UV and polariser) has no noticible vignetting effect on a cropped camera. Apparently the lens is designed to take a single filter, according to my mole inside Tamron.