Hi David, here is what I see at this canon europe link
Canon EOS R5 specifications and key features in detail.
www.canon-europe.com
JPEG: 2 compression options RAW: RAW, C-RAW 14 bit (14-bit with Mechanical shutter and Electronic 1st Curtain, 13-bit A/D conversion with H+ mode, 12-bit A/D conversion with Electronic shutter, Canon original RAW 3rd edition) HEIF: 10bit HEIF is available in HDR shooting with [HDR PQ] set to [Enable] Complies with Exif 2.31 and Design rule for Camera File system 2.0 Complies with Digital Print Order Format [DPOF] Version 1.1
parsed out,
H mode, MS or EFCS : 14bit depth
H+ mode, MS or EFCS : 13bit depth -- makes sense, to shoot faster need faster sensor readout, so drop 1 bit of resolution and tradeoff with a slightly lower SNR
ES : 12bit depth -- same as above, need to read faster
As an aside .. I see posters here asking for ES options for 10, 20, 30 fps .. but the readout still has to be done in the same amount of time to prevent rolling shutter effects, so ES will stay at 12bit ... I think.
I can't wrap my head around the power requirements between these modes though. if it was the electronics pathway from sensor to card that was power hungry, ES should have also degraded at lower than 50% batt levels, but it doesn't. I mean I get performance degradation at low batt levels, but 50%