Saturday, January 17, 2015

Comparison of Canon 400mm prime and 100-400mm zoom

The images below are from a test of our two birding lenses, the Canon 400mm f/5.6L USM prime lens and the Canon 100-400mm f/4.5-5.6 IS USM (Mk I) zoom lens. The tests were shot from positions 2ft apart of a stationary target 20ft away. The log target has fine details similar to a bird.
Test images were taken with the same Canon 7D II camera set to fine resolution center AF and exposed at f/5.6, 1600sec, ISO-800. Both shots were taken on a tripod with a cable release but mirror lockup was disabled. IS was turned off on the zoom lens. The CR2 images were imported into Photoshop CS6 with the default conversion parameters. Same 100% crop was applied to both images but no further processing performed. Images were saved as a single highest resolution 8bit JPG at original resolution. Both contrast and resolution are clearly superior in the prime lens. Though this difference is not critical for frame-filling subjects, it is noticable on tight crops of small birds.


  1. You probably already know this, but the new Canon EF 100-400mm IS II looks to have significantly better MTF at 400 - similar to the 400 prime - and has IS. Not cheap at $2200 but might be worth it. See comparison at

  2. The initial reviews have all been glowing as well. Might also address the other issue with the IS.


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