Having seen the reviews and checked out the footage, we’re afraid we’re going to have to take a hard pass on the long awaited a7 IV. The colors aren’t as nice, it appears to have worse underexposure latitude, the rolling shutter is pretty awful and there’s that 60p crop. For reasons they couldn’t pinpoint, CVP found that exposure varied significantly between the a7 IV and the a7s III. The a7s III measures white balance more accurately than the a7 IV due to the Visible Light and IR sensor. The lack of a stacked sensor would account for the abysmal rolling shutter performance of the a7 IV – a massive 26ms at 4K 24p! It may seem like nitpicking, but we’re not seeing any mention anywhere of the very useful feature, found on the a7s III, that displays a red frame around the edges of the camera’s monitor while recording a movie, warning the operator if the camera isn’t rolling. Perhaps most of all, the lack of ProRes RAW support is a dealbreaker. On the other hand, the focus breathing compensation is unreal, and it’s hoped that Sony adds this feature to the a1 and a7s III in a future firmware update. At the same time, cropping in on the 10 megapixel sensor area might degrade the image too much – and it’s unclear whether the feature works with ProRes RAW. Meanwhile, the a7s III is still pretty spectacular once the colors are balanced and to be honest, we haven’t seen any footage from the a1 that surpasses it.
Update: Sony has since released a firmware update that adds focus breathing compensation to the FX6, which shares the same sensor and processor as the a7s III – and it’s been confirmed that the feature is not compatible with ProRes RAW recording.
Download Sony a7s III ProRes RAW HQ 4.2K 23.976 HDR sample footage here.