A versatile fisheye zoom lens offering a choice of full frame or circular image the ef 8 15mm f4l fisheye usm is part of canons high performance l series lenses and delivers fantastic image quality even with such a wide angle view theres no need to buy two specialist lenses when the ef 8 15mm f4l fisheye usm offers either full frame or circular fisheye images when used with cameras with a 24 x 36mm full frame sensor for photographers shooting with dslrs with a smaller sensor full