Test of a Sigma AF 12-24 mm f:4.5-5.6 EX DG zoom on a Canon EOS 5D The Sigma AF 12-24 mm f:4.5-5.6 EX DG zoom provides the widest possible rectilinear field of view on a 24x36 mm camera, like the Canon EOS 5D, or a 1.3x cropping camera, like the EOS 1D-series. At 12 mm setting it provides an impressive 292 percent hFOV or 111° hAOV. The lens was tested at different focal length and at different f-stops using a Canon EOS 5D set at ISO 100.

 

The photographed scene:  The Greenhouse in Copenhagen Botanical Gardens
Shot @ 12 mm and f/11	Shot @ 24 mm and f/11

 

The camera was tripod mounted. Images were captured as RAW and converted to 24 bit TIFF files using DPP 3.0.0.3. Sharpness was set to 0 (no sharpening) and no other post processing has been applied to the images. 200x200 pixel crops were excised from the centre, midway and periphery and saved as TIFF prior to conversion as JPEG files.   The comparisons 12 mm - 15 mm - 17 mm - 20 mm - 24 mm - Summary