Arrived at lunchtime. Ugly thing, but reassuringly weighty. No lens hood supplied, which is pretty reasonable considering that it does 180 degrees corner to corner at 10mm, meaning the hood would have to be so short as to be practically useless, but it comes with a decent lens cap that probably won't fall off all by itself. (I have never liked the Canon ones.)

I mounted it on a 40D just now and had a play around the office. It has a nice solid feel to it and smooth, firm movements. One thing that could bug a lot of people is that the zoom ring is backwards - or frontwards if you are a Nikon user - you twist clockwise to zoom in. This would have bugged me a lot once upon a time, but doesn't seem to anymore because it's less of a distraction than the way that different lenses swap the positon of the zoom and focus rings.

The Canon EF-S 10-22 has a rear-mounted focus ring, and front-mounted zoom ring, while the 18-55 IS and the 24-105 have front-mounted zoom rings and rear-mounted focus rings. The Tokina is the same as the 24-105 (front focus, rear zoom ring). Although it rotates in the "wrong" directions, my initial impression is that this will be a lot less annoying than the front/rear swap that the 10-22 does.

Some people might wonder what my point is here. Well, the way I see it, the less you have to think about the equipment, the more effectively you are able to think about composition, lighting, stuff that matters. The sooner lens manufacturers put the same things in the same places (front or rear, I don't care, just so long as it's always the same) the better. But the clockwise/anticlockwise thing doesn't seem so intrusive as the frontwards/backwards location of the rings.

Focus takes place at a moderate pace, not notably fast, not notably slow either. Actually, to go the full range from infinity to the very pleasing close focus distance of just 14cm (less than 6 inches) takes quite a while, but with a focal length this short, you are already at or pretty close to infinity most of the time, so in practice it is likely to be a non-issue. The focus motor is moderately loud, not excessively so, and the manual focus ring turns during auto-focus. Given the nature of the lens, I can't see any reason why this should be a problem. There is no filter thread in any case, nor could there be without causing vignetting.

Never having looked through a fish before, I was pleasantly reassured to see that the view isn't wildly different to that of an equally wide-angle rectilinear lens, particularly if you keep it reasonably horizontal. First impression - I am yet to press the shutter button in anger with it - is that I should be able to use this thing quite a bit. At the 10mm end it's very distorted near the corners, but so is any 10mm lens. Short of scrapping the laws of physics, you can't fit an in-the-round scene onto a flat sensor without distortion: the 10-22 distorts it one way, the fish distorts it a different way. We wil have to wait and see, but I shouldn't be surprised to discover that most scenes that work well at 10mm on the 10-22 will work pretty well on the Tokina fish.

At 17mm, things are rather different. The fisheye look is much reduced and (depending on what you point it at) the casual viewer may very well not notice that your lens was anything abnormal.

Anyway, it's a nicely made lens, well-presented, and pleasant to hold. As for the pictures it takes, we will have to wait and see!