Sigma 12-24 - Can you use polarizer?

I'm looking at using a 12-24 on a 1.3x lens to get some wide angle for landscapes. It appears that you can't use a polarizing filter on this lens- is this correct?

It just seems hard to believe that there is no polarizing option on a lens whose focal length make it one of the lenses that you'd most want to use a polarizer for.

I searched the forum and didn't read about anyone commenting on this so what am I missing?

This is the only lens that can go ultra wide on a 1.3x w/o cutting up a 10-22, right? I'm used to the 10-22 on a 30D and don't want to be stuck with a 16-35 on the IIN loosing all that width.

No you can't...

You can use one (82mm) with the included front support but it will vignette like crazy..
So it's application is rather small...

Maybe check the Sigma 15-30? or Canon 14/1.4L

Sigma 12mm on 1.3x w/filter cap, no filter:

HTTP response: 404 | MIME changed to 'image/gif' | Byte size: ZERO | PHOTOBUCKET ERROR IMAGE

Raphael Emond wrote in post #3723925
Maybe check the Sigma 15-30? or Canon 14/1.4L

The 14mm L is f/2.8

You need a good tidy up there mate

Nick_C wrote in post #3724049
You need a good tidy up there mate

Everything has its spot. Where you see it is where it goes.

cdifoto wrote in post #3724050
Everything has its spot. Where you see it is where it goes.

Where it lands it stays aye! lol

Nick_C wrote in post #3724064
Where it lands it stays aye! lol

Roger that.

cdi is right. I have the 12-24 and it does exactly what he says on the 1Dmk2 with the cap sleeve in place. The only workaround I can think of would be to hold up a polariser made for drop-in systems in front of the lens. I've done this with GND's and while it's not ideal and you look a bit silly it does work.

I was thinking about this lens on the 5D, I could rule out using any filter then with this one.

Raphael Emond wrote in post #3723925
No you can't...

You can use one (82mm) with the included front support but it will vignette like crazy..
So it's application is rather small...

Maybe check the Sigma 15-30? or Canon 14/1.4L

14mm f/1.4L!!!

On a more serious note, neither the Sigma 15-30 nor the Canon 14mm f/2.8L take front filters. Your choices for using a filter on wide angle lenses for APS-H are:
1. Canon 16-35mm f/2.8L
2. Sigma 10-20mm past a certain focal length
3. DIY-project for adapting Cokin Z-Pro filters to the Sigma 12-24 (I've seen it done...)

cdifoto wrote in post #3723941
Sigma 12mm on 1.3x w/filter cap, no filter:

HTTP response: 404 | MIME changed to 'image/gif' | Byte size: ZERO

The 14mm L is f/2.8

Don- I'm confused as to why you are getting that look compared to the way it looks in the lens archive (ignore first pic on 10D and scroll for the lens an 1.3x and FF cameras)
https://photography-on-the.net/forum/showthre​ad.php?t=298928

I've been under the impression for a long time that this is the best ultrawide for a 1.3x camera unless you want to settle for 16mm as your starting focal lenght. Is there a better solution?

Rich, the 12-24 comes with a slide-on sleeve that covers the petal holder and is what you clip the lens cap into. The front of this sleeve is threaded for filters and that pic shows what it looks like on a 1.3x when the sleeve is attached. If you remove this sleeve for normal shooting then there is no vignetting from the remaining fixed petal hood.

[edit] You can see the sleeve on and off in the photozone review.

I used to think that it was odd that the 12-24 could not be used with filters but it was pointed out to me ( probably by someone on this forum ) that when a polarizer is used at these FLs ( especially on full frame )the sky darkens unevenly and a graduated dark to light blue look is all that's achieved - often quite undesirable. Should I ever pick up a UWA then I think I'll stick a with photoshop correction.

Before changing your lense or bodging a lense decide weather this is something you'd be happy to live with, although on a 1.3X the effect won't be as pronounced as with a full frame.

incidentally the tamron 12-24 I believe can be used on a 1.3X with only a small amount of vignetting wide open at FLs below about 15mm and it takes filters. This may be the way to go.

oh and it's F4 too and stopped down a bit vignetting shouldn't be a problem

I usually just crank up the blue channel in Lightroom to the point of making the sky awesome but not throwing anything in the ground out of whack.

RichNY wrote in post #3723278
I'm looking at using a 12-24 on a 1.3x lens to get some wide angle for landscapes. It appears that you can't use a polarizing filter on this lens- is this correct?

You probably would not want to use a polarizing filter on an ultra-wide lens even if it could be mounted properly. Why? With a wide-angle lens, you take in the sky across such a wide viewing angle that the amount of darkening of the sky (by the polarizing filter) changes radically across the image. This is because the amount of polarization of the sun's light varies with the angle to the sun.