Canon have a new ultra wide, the full frame 11-24mm f/4 L. I'm surprised there is not a thread about it yet.
The good news:
- 11mm at the wide end on full frame! That's even wider than the Sigma 12-24. In fact, the widest full-frame rectilinear lens ever made.
- Constant f/4.
- From specs and early previews, stunning sharpness, outstanding flare and and distortion control.
The bad news:
- Rear-mount gel filters only. The front element protrudes too far for orthodox filter use.
- Very big and heavy
- Jaw-dropping price. Apparently, it contains the largest series-production ground aspherical lens element ever made. At (from memory) 87mm, it's way larger than anything similar, and it's ground, not moulded. Grinding aspherical lenses is very difficult and expensive. Doing one this size ... well, that's no doubt why you are looking at over $4000.
More here: http://www.the-digital-picture.com/R...-USM-Lens.aspx