Nikon’s last low light monster, the D750 has finally been knocked off the hill. The new Z6 and Z7 with their new BSI sensors have overtaken the D750 to hold positions 1 and 2 for low light performance, at least for exposure times below 30 seconds. Our testing showed at 300 seconds (5 mins) the Z6 and Z7 were significantly worse than the D750, as well as many other models. At what point the sensor introduced the noise is yet undetermined, I expect well above 30 seconds.
So for any application below or at a few minutes the Z6 is going to be better than anything currently available in the market. There is no evidence of star eating, and NR off in camera appears to be “off” unlike some other bodies that add grain or manipulate the RAW data even when set to “NR Off”.
The Z7 is still great at 1 second, but starts to fall away when compared to the D750 @ 30 seconds. Keep in mind this is a 46 v’s 24 mega pixel race. So the Z7 performs exceptionally well for its pixel count. At 30 seconds I expect you would be getting wonderfully clean images in low light.
The Z7 seems to perform slightly better at 300 seconds compared to the Z6, which was a bit of a surprise, and it was also out performing the 5DSR and GFX-50S. It was about the same as the A7RmII (I do not have the mIII sample as yet).
If you are looking for exposures in minutes, then I’d maybe consider other bodies. But keep in mind the new Z mount may see some faster glass in the future, which would allow a reduction in ISO, and possibly a more cleaner image, and it is 46MP after all.
Overall it’s a very impressive result, and continues to show that Nikon are working hard with Sony to produce sensors that give exceptional results in low light / long exposure situations.
To compare more models, or see further details, check out the Sensor Database.
A big thanks for Alex @Stallards in Hobart for access to the Z6 and Z7 for testing.