Firmware Version 1.0.4 for the EOS 5D Mark IV incorporates the following fixes and improvements:
1. Fixes a phenomenon in which a red-coloured area may appear at the bottom-centre of a captured image when shooting in bulb mode or during a long exposure.
2. Fixes a phenomenon in which the autofocus may not respond when the autofocus is initiated via pressing the shutter button, the AF-ON button or the AE lock button when configured in the custom control menu.
3. Enhances the reliability of communications between the camera and SD card.
4. Fixes incorrect wording on the Finnish language menu screen.
The firmware can be downloaded at: