Victor, thanks! Knowing that I can add 77mm filters is really helpful. How do you like the lens for video and for stills?

1) Ken Rockwell is a Nikkwhore.
2) Screw on filters are for photographers and hippies. We are cinematographers and thus use 4x4 filters on matte boxes, which work fine.
3) It's only 5.6 at 24mm, who cares about the boring end? It's f4.5 at 12mm, which fine is still kind of slow... but so what, it's 12mm! (and his review is flawed, stating that the Canon and Nikon 10mm and 12mm lenses are better, but since they are both EFS and DX lenses and the Sigma is full frame, they aren't in the same category).
4) Also, I heard Ken Rockwell punched a puppy and drinks light beer... so... I'm just saying...

I picked up a tamron 20-40 f2.7-3.5 in nikon mount since I had been looking for a tamron 17-35 2.8-4 based on good reviews but everywhere seems to be out of stock in for that lens in nikon mount. I had seen the 17-35 reviewed in comparison to canon and sigma. These tamron lenses provide comparable quality to canon especially when using as manual focus so usm is no concern, and all sigma superwides with reasonable prices seemed extremely lacking in sharpness bad for distortion based on reviews I read. The tamron 20-40 was incredibly cheap used. its ~$150 and keh has it, but i picked one up at adorama in person since i wanted it sooner. after some use ive been very impressed with the sharpness and lack of distortion (for the fov) on my 5dmk2. I used it a lot on a 48hr film fest entry last weekend and love having such a wide lens. I shot some photos and video this week on top of the empire state building and I just have to say it is insane not to have a lens at least this wide if you are shooting landscape exteriors. It's a pretty amazing look shooting at f2.7 at 20mm and being in a Medium-Full shot and still having the background quite blurred out despite the wide angle. Feels like an even larger format. Only thing to be careful about is flare, it doesnt flare too pretty and at 40mm it still flares like a 20mm. I had to be careful with this on some heavily backlit stuff I shot. Only problem ive found is backfocus, though thats probably my nikon-eos adapter. i have a cheap ebay kawa adapter and an even cheaper ebay hongkong adapter, and both seem to be too short in depth, so the lens focuses quite a bit past infinity.

i should mention my original choice of the 17-35 tamron was based on reviews at the fred miranda reviews site, but they had no reviews for the 20-40 which i eventually came across on my own and looked up reviews which seemed to be quite good.

what about the Tokina 11-16mm, just bought one for my Red that is being converted to PL mount as I type.

Noah, thanks for the heads-up on this lens that I had never even heard of as I have been looking for a wide zoom. After looking at a few pretty decent reviews I started looking on eBay & amazingly found a Canon mount one for auction here in France with just 4 hours to go. I won it at 200 Euros (about $285) including shipping & should receive it next week. On the various eBay sites that I looked (UK, France, Germany & US) there were a few Nikon mount ones available for a around the same price but the only other Canon mount one was 400 Euros ($570) so if I don't like the lens maybe I can turn a profit:-)

Nikon 14-24G > Contax N Zeiss 17-35 > Nikon 17-35 > Canon 16-35 > Third Party

Jon:

You asked <<What adapter is needed? Is it really an f/2, or does the falloff andcontrast loss get extreme? How's it look with your filter system? Does the front move when you focus? What's the typical price range? >>

I'm using the eBay sourced 'Big-iS' EOS-OM adaptor from Hong Kong. An 'AF Confirm' type adaptor (beeps when in focus) and it now comes in a version that can have the lenses EXIF data inputted to the adaptor...via a sequence of shutter and aperture 'fiddles' to set the adaptor for the lens.
A great idea but since I'm using 6 Olympus lenses with one adaptor probably not too relevant.
Not all adaptors are equal, a matter of the machining tolerances. Fotodiox do an expensive adaptor and there are some rated Japanese ones.No Novoflex though.

In the wide angles, I have the 21mm, 24mm and 35mm Oly lenses which are all f2.0 versions, so great for video work.

There are users posting on the web, like this one:
PixelPix by Russell Stewart: Tip 8: Olympus Lenses on your Canon SLR

There obviously is some fall off on the 21mm but I guess the Nikons have that too.
Software can take that out on stills...but it's hardly noticeable on video to be honest as narrow DOF helps the eye in video.
The front elements do move during focusing.
I'm using the Cokin P Filters and have the 'wide-angle' holder which avoids vignetting....just I guess. Mostly using ND8 (3 stops ND) because of video exposure in daylight and have the older Cokin A filters on the narrow lenses.

Oly manual lenses are prized for sharpness so keep reasonable prices and the 21mm f2 is sought after, I'm not sure how much you'd pay locally though.
David T.

It gives a strange sort of perspective. I really like it for having the subject relatively close to the camera and off center and it will give huge panorama of the background with just a hint of fisheye effect. Its really light and discreet as well for more street shots. I do a lot of solo work in urban settings and I like a rig that doesn't scream "steal me". I am finishing a video project this weekend that I can try and post on youtube some examples of the 20.

I am on a waiting list for the new 17 TS lens... That will be really nice lens I think.

How about the Canon EF 14mm f/2.8L II Rectilinear...

At $2k+, that looks like a fine rental.

I've got a concept that would include timelapse and astronomical shots, and that lens is at the top of the list for that job...

I went with the Tamron 17-35mm f2.8.

I was gonna go with the Canon 17-40 f4,
but the Tamron was only $300 and it was f2.8.

I'm satisfied with it.
Having the f2.8 is nice.

It is soft in the edges but not an issue for video.
For stills it could be, but only if you're really blowing up your photos.

-Bill

That might just be my purchase - to go along with the occasional 14mm rental.

A couple of questions:
* Have you tried it with filters? (I like the 77mm thread, btw)
* Does the contrast die, when you go to f/2.8? (Some lenses seem to go dark when you open them that last click - which defeats the purpose of the large aperture.)

Thanks!

Just a reminder that the 5DII's Peripheral Illumination Correction doesn't work with Tamron lenses (or any 3rd party lenses). This is a reason to consider staying with Canon, especially with an ultra wide lens where vignetting is a factor.

Jon,

Sorry to come to this late, I would seriously suggest you look at the older Nikon 20-35 f2.8 AF lens. It can be found quite cheaply now and features better manual focus than the newer lenses, importantly it also has hard end stops and a 77mmm filter thread.

The other sensible options are the Nikon 17-35mm f2.8, Canon 17-40 f4 and 16-35mm f2.8 II lens.

Dan

AGREED!! I researched the Sigma 12-24mm like mad on flickr and was sold.

Flickr: Sigma 12-24

Cheaper than the Canon 17-35, and I feel way more satisfied having an extreme wide that's not fish-eye.

Regarding it's slow aperture, I really don't care. I have other fast lenses for stupidly low light. This thing does just fine with a modest amount of light on the 5DMkII.

-steev