Update 2014-08-16: Premiere Pro had been interpreting the GX7 footage as interlaced, causing aliasing. I've now fixed this and replaced the video here. You can also download the full quality 336mb render by clicking "Download" below (you must be signed in first though).
In early April I bought a a6000 temporarily to do some tests and satiate my curiosity about whether or not it could replace my GX7. The larger sensor and nice grip, along with stabilized 35mm and 50mm lenses were attractive to me.
All shot at 25fps with similar picture profiles and dynamic range settings, though the outside clips may have had more shadows lifted on the GX7. Noise reduction and sharpening were turned off on both cameras.
Sony clips are first and have had their white level pulled down from 255 to 235 to bring out some highlight detail that would otherwise be hidden.
- The Sony has a noticeably higher moire and aliasing issue on details like the bricks and roof in the first shot.
- The Panasonic has much more detail, most notable on the face at the end, in which the Sony does not display any of the fine pores or wrinkles. Also check out the grass, fence and tree in the first shot.
- In extreme low light, the Panasonic still has slightly more detail, but the noise is also more distracting than the Sony. I believe this is due to Panasonic's more accurate readout of the sensor. Whereas the Sony by nature is softer anyway.
- Both cameras are pretty accurate colour-wise and can be dialled flat or whatever to your liking. However the a6000 has trouble keeping highlight detail.
Finally, there are a couple of distinct advantages of the Panasonic's detailed video. I can digitally stabilize and rescale without the image becoming really soft. I can denoise without losing too much detail. And I can use budget lens filters without worrying that they'll degrade my image a lot.
In the end I kept the GX7 because I felt the a6k would be a downgrade in video quality and also it had a worse menu system and controls. Also the RAW didn't really seem any better. See raw files: sebcastilho.com/uploads/a6000vsGX7_raw_photos.zip