I don’t even shoot canon anymore, but I’m still active on PotN and have the shots of this project so I figured I’d share this officially (this shots are buried in a 17-40 post here somewhere). Basically, canon uses the same hood on the 17-40L, 16-35L (but they made it even bigger for the 16-35II!) and 10-22. In all cases it’s VERY wide but also VERY shallow for what you’re doing. This also makes it hard to store in a bag easily. There are 2 options for those of you that like DIY projects though, get yourself either the 24L (original, not sure on the 24L II) or 24-105 hood. Get your dremel out and remove about 2mm all the way around. The hood will be slightly less effective on either of those lenses now, but MUCH more effective on your UWA and it will also fit in your bag MUCH better.