Canon EF 17-40mm f/4L Test for Sharpness in Images
Comparisons
at 35mm with EF 35mm f/1.4L
Also, 35mm equivalent taken with EOS 20D and EF-S 10-22mm lens
Images were taken on the same day at f/11 aperture priority and at ISO 100 in RAW mode and automatic white balance. RAW files were converted to 300 dpi tifs with Capture One Pro v. 3.6. The tifs were enlarged in Photoshop 7 to 20 inch wide tifs, sampled and samples converted to 72 dpi jpg's. Sharpening and unsharp mask was used to optimize image sharpness.
Note: The upper right edge shows the greatest difference in lenses with the L-prime being the clear winner at 35mm equivalent.
Note: Test photos taken during variably breezy morning. Don't pay too much attention to leaves and very light foliage that is moving in the breeze.
35mm or Equivalent
| Camera / Lens | Full Frame - 35mm or 35mm equivalent | Crop 1 - Left Edge | Crop 2 - Upper Right Edge | Crop 3 - Center |
| EOS-1Ds EF 17-40mm f/4 @ 36mm & f/11 |
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| EOS-1Ds EF 35mm f/1.4L @ f/11 |
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| EOS 20D EF-S 10-22mm @ 22mm f/11 |
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