This is a very well built lens, solid, with a good finish. The lens coating is impressive, and worth the manufacturer claims. It was introduced in 2006 and was one of the very first available choices if you wanted to have a fullframe fisheye on an APSC sensor sized reflex camera. The image results are very good, if they are not totally impressive, due to a bit of CA and some softness at the borders. It gets to its best at f8.
It’s the same lens scheme as the Pentax 10-17 one, first product of Tokina-Hoya and Pentax cooperation. It gives a nice choice in apsc, to use a fullframe fisheye covering the whole sensor, or… clipping more of the field of view going from the 180 degrees on diagonal to 100 on a nikon/sony DX sensor, a bit less on Canon 1.6x.
The uncommon behaviour of this lens is that it extends from a diagonal fisheye to a cropped full-frame fisheye, when used on the APSC sensor it was designed for, mimicking the first fisheye zoom ever, SMC PENTAX-F FISH-EYE 1:3.5-4.5 17-28mm.
At 17mm it resembles a super-distorted wide-angle, but it’s still a fisheye! so it comes very handy for two reasons, in 360 VR panorama production, if you use it with a multirow panoramic head you will have an impressive boost in resolution shooting more pictures and gaining a bit of angular resolution (two rows of 8 plus zenith is a good compromise).
The company says the FOV is 180° to 100° on a 1.5X sensor (Sony-Nikon etc.) I can confirm on the Canon 1.6X is a bit more like 160°.
10mm 
15mm 
17mm 
There are other versions of this lens. Remind me to put some link.
This lens is very commonly used in underwater photography.
Since it was one of the first available, so there are many specific domes, ports, and housings.
Nimar
Nauticam
links
- – Michael Thoby page on the lens
- https://www.uwphotographyguide.com/tokina-10-17mm-fisheye
The lens is currently AVAILABLE IN THE MARKET - pruducer’s page for the Tokina 10-17 DX
