Old refers to the 75-300mm f/4-5.6 II, while new refers to the 70-300mm f/4-5.6 IS USM. Pictures were converted from the 7D’s full resolution RAW to JPEG with identical settings, aligned in Photoshop, then cropped to a 480x480 pixel section at 100% zoom.
The images presented are taken at ISO 1600 in the middle of the field of view, approximately from the area highlighted here:
I bought my first camera, a Canon EOS 300 35mm film body, back in 1998 along with a 28-80mm f/4-5.6 lens and 75-300mm f/4-5.6 II lens. These are both “consumer grade” lenses which came as part of a kit, but they fared me very well for a good number of years.
