Image Quality

While the GX7's image quality looks good in most situations, we did notice a troubling issue that occurs when shooting in Auto or Program mode. When shooting in brightly lit situations, the GX7 will stop down the aperture - often to F9 or F10 - instead of increasing the shutter speed. At those apertures, diffraction is an issue, which leads to softer images. We hope that Panasonic can adjust this issue in a firmware update, as it is negatively affecting image quality.

Another issue is the GX7's tendency to clip highlights rather abruptly. You can smooth out the transition to white by using one of the i.Dynamic modes, which also expands the overall dynamic range of the camera. Check out the graphs on our DR page to see for yourself.

The GX7 does a nice job of capturing vivid colors. If you want to adjust the color saturation to your liking, you can do so via the Photo Style feature.

ISO 200, 1/800 sec, f/7.1

The GX7's colors are nicely saturated, without going overboard. Color accuracy is fine in most situations, though the auto white balance system struggled a bit in artificial light. As with all cameras in this class, the GX7 offers white balance fine-tuning, as well as WB bracketing.

Panasonic has found a nice middle-ground with sharpening on the GX7. It renders fine detail pretty and rarely shows signs of over-sharpening.

ISO 200, 1/500 sec, f/3.2

Panasonic has done an admirable job in finding the right balance when it comes to JPEG sharpening - fine detail is reporduced pretty convincingly with little sign of over-sharpening halos on high-contrast edges.

JPEG
ISO 200, 1/800 sec, f/6.3
Raw
ISO 200 1/800 sec, f/6.3
100% Crop
100% Crop

The GX7 produces fairly sharp images, without too much detail smudging. There a little improvement to be had by shooting Raw and adjusting sharpness to your liking. We feel the above example (processed with a sharpening radius of 0.8 pixles and amount set to 48 in Camera Raw) gives a slightly more 'realistic' rendering, though we're not really gaining any additional detail.

As shown in our noise test, the DMC-GX7 has a bit more noise than the competitors we chose, though that may be due to the Panasonic's light application of noise reduction. To see how the JPEGs look at high ISOs, we offer the example below (which also shows the advantages of Raw).

Original JPEG, ISO 12800, 1/20 sec, f/5.6
Original JPEG, 100% crop Raw conversion 'to taste', 100% crop
Original JPEG, 100% crop Raw conversion 'to taste', 100% crop

As you can see, the JPEGs at ISO 12800 can be pretty mushy in terms of detail. There's also what looks like false color around the cat's eye. By converting the Raw image using Adobe Camera Raw, we're able to restore some of that fur, remove the false color, as well as tweaking the white balance while we're at it.