Image quality

Processed in Adobe Camera Raw | ISO 100 | 1/250 sec | F8 | Zeiss 16-70mm F4

Key takeaways:

  • Raw performance is all but identical to the older a6300
  • JPEG performance however, has broadly improved with more pleasing color and even better high ISO noise reduction

Studio scene

Our test scene is designed to simulate a variety of textures, colors and detail types you'll encounter in the real world. It also has two illumination modes to see the effect of different lighting conditions.

The main story here is that, in a nutshell, image quality is identical to the older a6300 in Raw mode. We can first see this in terms of detail capture throughout the scene. There are instances of moiré visible from all of the Bayer cameras here, with Fujifilm's X-Trans sensor tamping that down somewhat. As ISO values climb, we can see that the Sonys and the Fujifilm perform similarly, with the EOS M50 falling just slightly behind.

The JPEGs, however, tell a slightly different story. Default JPEG sharpening at lower ISO values is still very similar between the two Sony cameras. But, a close look at our ColorChecker shows some differences regarding color rending. Compared to the a6300, the a6400's reds and yellows are a bit richer, and the greens a bit warmer. Color preferences are subjective of course, but for our tastes, these are improvements - particularly for landscape and people photography. Also, when the ISO value creeps up, Sony seems to have tweaked their noise reduction as well. There is a bit more grain, but a bit less mushiness; this is borne out by differences in the dead leaves pattern as well.

Raw dynamic range

Our ISO invariance test shows that the a6400's sensor is a good performer, just like the a6300. There isn't much of a difference between shooting a scene at the base ISO of 100 and pulling the shadows up by 5ish stops, versus shooting at ISO 3200. For advanced users, working this way can help keep the brightest highlights you want to preserve from clipping to white and being unrecoverable.

Now let's look at exposure latitude, in which we use the camera's base ISO and try brightening increasingly dark exposures to see how much noise is being added in the deep shadows. Here, you can see that the Sony a6400 is adding a little less noise to its images than its main competitor, the Fujifilm X-T30.