In preparation for the assignment, I read Norman Koren's "tutorial" on lens testing here
and quickly decided to leave lens resolution testing to pros like Norman. My approach was more utilitarian and perhaps reflective of real-world shooting experience.
I downloaded a resolution chart, snipped out the horizontal resolution part, pasted it onto the back of Photoshop Magazine, clipped it onto a box of Ilford Galeries Smooth Pearl Paper, propped up everything on a convenient spot in our sunporch, attached my 10D to a sturdy tripod (as instructed), mounted the 85/1.8 followed by the 70-200/4.0, and fired away (RAW captures) ignoring all advice about mirror lock up and other niceties. I then RAW processed, added a little sharpening (controversial, I know), and cropped out the resolution chart.
Here are the 100% crops. The uncropped image is in the lower left corner. Except for the 85mm @ f/1.8 (which ain't bad), I think the results are about the same for both lenses. Surprising to me!
I went out later in the day and snapped this shot of a young lady at a neighborhod fair with my 70-200/f4 @ 200mm f/8.0, 1/500, ISO 200.
I searched my files for a similar shot with the 85 mm, cropped out the eye (100%), and made this comparison with the above shot. Note that the shooting conditions are quite different. But in terms of sharpness, the results again are quite similar.
That's my first and last attempt at lens comparisons. Comments welcomed. Criticism will be appropriately filed.
