How did they do this?
Canon has specified in the latest EOS R5 information that the camera will shoot 8K DCI, which is 8192×4320. Since Canon has said that 8K recording uses the full width of the sensor, the sensor would be 8192 pixels wide. Canon sensors use a 3:2 aspect ratio, so that would mean the height of the sensor is 5461 pixels, which equals 44.7mp.
I’ve been reporting for quite some time that the image sensor would be 45mp, so this seems to back up those long-running rumors.
If the math is wrong, please let me know.