Stay alert, control the camera, save photos
- Aug 16, 2012
IMPORTANT EDIT: Canon has out-of-date MTF charts listed on its USA site for some lenses. Thanks to alerts from subsequent posts, I have gone to the Japanese site https://cweb.canon.jp/eos/ and have revised the charts and conclusions. The opening post has been rewritten so as not to mislead and I have added data from the EF and RF extenders which are available only on the Japanese site. Canon can be a real pain in revealing data, which are hidden away in Japanese. They now no longer give stopped down data and I cannot find whether they use diffraction corrected values, but I guess that they do comparing some Sigma values with and without corrections with Canon's. I hope this compilation is useful to those considering purchases.