This is a follow-up to vimeo.com/35111205, which shows that the 3x digital zoom on the Canon 600D/T3i can be used to eliminate (or at least greatly reduce) moire.
Because of some very informative comments on the video in the Magic Lantern Users Group (notably from Ilya, a1ex, and Andy600), I wanted to see how the apparent resolution of the 600D/T3i depended on a) the lens and focal length; and b) the use of 3x zoom; if at all.
So, my wife generously sacrificed a 13x19" sheet of photo paper and printed a resolution chart (@ 19" wide) on her Pixma 9000mkII, which came out quite well. The chart is from: graphics.cornell.edu/~westin/misc/res-chart.html. We stuck it to the wall (actually, a door) and shot away.
The video was shot in 1920x1080 24p on my 600D/T3i, with the above-mentioned lenses at ISO 320 (using Magic Lantern). I attempted to frame the shots as well as possible so that the 16x9 area of the resolution chart matched the recorded area on the camera, using the camera's LCD screen only. This required me to move the tripod on my less-than-level floor, having to try to find level each time. I did try to match the center of the lens height to the center of the chart, etc. The end result is not perfect, but it is a somewhat controlled environment...
The video starts with a photograph of the chart using the Zeiss and scaled in photoshop. This is intended as a reference so that the remaining shots, all video, are comparable to this. I take this reference shot to be the "best". My take is that we really can't judge much by the absolute numbers on the chart, since so much is going on, including the scaling to 720p and the recompression that vimeo does. But, we should be able to compare among the shots in this video. I've tried to render this out carefully, using Vegas to edit and output at 1920x1080 and Handbrake to scale and encode to 720p mp4. There is no audio.
I'm interested to hear your thoughts and observations.
By the way, I don't make more of this than it is. Myself, I'm a "does it look good in the real world?" guy in the end. But, this is something I wanted to test to help inform my lens and shot selection.
You might also be interested in a follow-on video that I did to compare the 600D/T3i with the 550D/T2i using these resolution chart shots at vimeo.com/35540004