Here is the extreme low light video test. There are more comparison videos coming up. So, stay tuned to the channel. Notice the framing between these two very comparable systems in terms of FOV and bokeh? It is not as simple as we thought. I will discuss more on this in a future video. For this test, shutter speed is the key!
I am testing the high ISO performance for proper exposure between the a6700 and the A7Cii recording 4K 30 FPS on both these cameras as that is the maximum allowable framerate by these cameras without a crop with maximum image quality.
While you are watching the video, pay attention to the AF box on the bottom left screen. At very low exposures, the Autofocus struggles. AF functions properly from ISO 800 in the A6700 while it functions properly from ISO 400 in the A7Cii.
I am honestly blown away by the fact that the A6700 footage at ISO 12800 is very usable for the kind of content I make.
For comparison: I find A7Cii is 1.5 stops better than A6700 in high ISO performance. I cannot quite compare with the 1.5 stops so I compared with 2 stops. ISO 12800 on A6700 with ISO 51200 on A7Cii.
REVIEW VIDEO
ISO 12800 in A6700 is same as ISO 32000 in A7Cii
This is a Sony A6700 Vs Sony A7Cii Extreme Low Light – Extreme High ISO Video Test Comparison!
QUICK SUMMARY
A quick summary of high ISO performance in Sony A6700 vs Sony A7Cii 1. They perform very well at base ISOs 2. Base ISOs of Sony A7Cii are ISO800 & ISO3200 for video 3. Base ISOs of Sony A6700 are ISO800 & ISO2500 for video 4. When subject is exposed at 0 EV, the performance is great 5. Rising shadows in a noisy video is a disaster 6. Sony A6700 performs very well up to ISO6400 7. Sony A7Cii performs very well up to ISO12800
KEY TAKEAWAY
USABLE ISO FOR VIDEOS
SONY A7CII
SONY A6700
BASE ISO 1
ISO800
ISO800
BASE ISO 2
ISO3200
ISO2500
GOOD RESULTS
Up to ISO6400
Up to ISO3200
USABLE RESULTS
Up to ISO12800
Up to ISO6400
USABLE ISO FOR PHOTOS
SONY A7CII
SONY A6700
GOOD RESULTS
Up to ISO6400
Up to ISO3200
USABLE RESULTS
Up to ISO12800
Up to ISO6400
GEAR USED
Cameras
Sony A6700 Sony A7Cii
Lenses
Viltrox 27mm F1.2 Sony 35mm F1.8
Microphone
RODE NT1 Gen 5
PRIMARY PHOTO CAMERA
SONY A7CII
SECENDORY PHOTO CAMERA
SONY A6700
PRIMARY PHOTO LENS
SONY FE 35MM F1.8
SECONDARY PHOTO LENS
VILTROX 27MM F1.2
WILDLIFE LENS
SONY FE 200MM-600MM F5.6-F6.3
PRIMARY WIDE ANGLE LENS
SONY E 11MM F1.8
CONCLUSION
The bottom-line is if you are exposing for the subject, you need to use the correct shutter speed. In that case, for the same shutter speed even with the brightest autofocus lens for the system, APS-C cameras can only fetch you noisy videos while the Full Frame camera may produce less noisy videos which is evident from these tests. But for me, I am totally happy with the video quality of the A6700 even at ISO 12800. I just need to use a bit of noise reduction.
SAMPLE PHTOS
Here are some examples of images from the Sony A6700 and the Sony A7Cii straight out of the camera (SOOC) JPGs.