Wide angle for 5d

Tokina 16-28 f/2.8

I also voted for the Canon 17-40. Sure, it isn't a high priced wide F2.8 aperture lens, but bang for your buck wise I think it represents great value. Even though mine would be my least used lens, I would never part with it as I would never want a wide F2.8 aperture on a UWA that is only used for landscape/urbanscape duties. The 17-40 delivers consistently sharp images with good colour. It also zoom in lens the same as my 70-200 which is a bonus as well.

So much choice...

Budget - I'd take the 17-40 or a Zeiss 28/2 or 35/2
Zoom - 16-35
Prime - Zeiss 25/2 or 21/2 or 35/1.4.
Tilt - TS-E 17 and add a 1.4x to give yourself another option.

Of these, I think the 25 or 28 are the most interesting.

picked up a 17-40 w/ my 5Diii. love it! thanks for the help guys! it is spot on to what I was used to with my 10-20 on my crop body

/M3Matt wrote in post #14441500
=///M3Matt;14441500]pi​cked up a 17-40 w/ my 5Diii. love it! thanks for the help guys! it is spot on to what I was used to with my 10-20 on my crop body

Just picked up my 17-40 a couple weeks back on my 5d3 as well and love it.

Sold my 12-24 that i used on the 7D for it.