"A wonderfully versatile lens that enables you to switch between circular and diagonal fisheye effects with a twist of the zoom ring"
- Dual circular and diagonal fisheye options on full-frame cameras
- very good image quality
- excellent L-series build quality and ring-type USM autofocus
- Lacks circular/diagonal versatility on APS-C and APS-H cameras
- fisheye distortion effect is minimised at 15mm on an APS-C camera
- very expensive for a fisheye lens