Sony 200-600 vs 100-400 Autofocus Test with 4 Cameras

In the following video featuring my dog Frank I do a simple autofocus comparison and keeper test.

This video forms part of my Sony 200-600 vs 100-400 comparison article.

I shot both lenses wide-open at 400mm, I then added the 1.4x to the 100-400 and tested it at 560mm vs the 200-600 at 600mm.

Because autofocus performance can vary so much from camera to camera I did the same test with the a6400, a7III, a7R III and a9.

Overall the 100-400 at 400mm had a keeper rate of 96% compared to 93% of the 200-600 at 400mm. However, the tables were turned when I added the 1.4x to the 100-400 which reduced the keeper rate to 92% at 560mm, this compared to 95% with the 200-600 at 600mm.

The a7R III had an overall keeper rate of 85% compared to 87% for both the a6400 and a7III. The a9 didn’t miss a shot with a keeper rate of 100%. Of course Frank is not the most challenging of subjects but he was the most convenient for testing so many cameras and focal lengths.

Here are some of the images from the test shoot. The light was changeable so it was impossible to balance the exposures perfectly between shots. I was also shooting in JPEG only so no RAW files I’m afraid.

Sony a6400 at 400mm

Sony 100-400 at 400mm with a6400 and German Shepard

Sony a6400 + 100-400 @ 400mm | 1/2000 | f/5.6 | ISO 800 | Full Resolution SOOC Download: JPEG

Sony 200-600 at 400mm with a6400 and German Shepard

Sony a6400 + 200-600 @ 400mm | 1/2000 | f/6.3 | ISO 500 | Full Resolution SOOC Download: JPEG

Sony a6400 at 560mm / 600mm

Sony 100-400 + 1.4x at 560mm with a6400 and German Shepard

Sony a6400 + 100-400 + 1.4x @ 560mm | 1/2000 | f/8 | ISO 1000 | Full Resolution SOOC Download: JPEG

Sony 200-600 at 600mm with a6400 and German Shepard

Sony a6400 + 200-600 @ 600mm | 1/2000 | f/6.3 | ISO 640 | Full Resolution SOOC Download: JPEG

If you download and take a closer look at the images you’ll struggle to spot much difference at 400mm between the lenses, but the 200-600 wins again at 600mm when compared with the 100-400 + 1.4x at 560mm.