The A7 IV can also use one CFexpress card (type A), but it is only worth it for specific needs.

Memory cards: dual SD card slots on both cameras.

Viewfinder / Monitor: more resolution and frame rates in the viewfinder, multi-angle LCD screen and more touch capabilities for the new model.

Design: subtle changes make the new camera more comfortable to hold, while also giving it more customisation and a better menu system.

Image stabilisation: there is a minor improvement for still photos, and the Active mode for video on the A7 IV is useful when walking with the camera.

Video: there are a lot of improvements on the new model including 10-bit 4:2:2, no recording limit, 4K 60p (crop mode), a bit more dynamic range and better skin tones.

The latter has a better buffer when using the expensive CFexpress Type A card.

Continuous shooting: the two cameras have the same 10fps burst speed, but that decreases to 6fps with uncompressed or lossless compressed RAW on the A7 IV.Eye AF also works in video mode, unlike the A7 III. Autofocus: the addition of real-time tracking and Eye AF for Birds is the major improvement.Image quality: the A7 IV has more resolution, a bit more dynamic range and updated colour profiles with better skin tones.

Sony a7 iii