Heating comparison with GX8
http://www.focus-numerique.com/sony-a7r-ii-chauffe-ne-chauffe-news-7626.html
ISO performance and DR tests
Just wait for A7s II. for now that you see is most wide and best paid promotion I saw in last years :-)
Seems to be quite attractive for photographers, but for video it looks like there is a serious overheating problem when recording internally. Since the A7S is using considerably less power when recording externally (with a device like the Shogun) it might be possible to use the A7R II for longer periods if not using internal recording.
This is only speculation on my side, but anyone tried?
Looking at teardown Sony still use extremely complicated designs, copper heatsink on image processor (see iFixIt) means that it can be made using very old process to increase margins.
Moving slowly upwards tripod shot. Sony A7RII v GH4 in camera card recording h264 streams. Sony left, gh4 right. GH4 has bigger B frame tables and slightly more (3%) better perceived signal to noise ratio.
Some low light samples
http://www.mirrorlessons.com/2015/08/14/sony-a7rii-image-samples-low-light/
Sony A7RII Overheat
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