If you have a PS5 you will have noticed one thing, the colors of old PS4 games do not reproduce as they should, something that can negatively affect the experience for the most purists in graphics.
PS5 does not play SDR content well
One of the problems that the PS5 seems to have is in its video output interface, if a few weeks ago it was known that it does not support HDMI 2.1 yet to be covered by bandwidth, being limited to HDMI 2.0. The last bad news has to do with the reproduction of SDR content, that is, content whose color palette is the classic RGB with 8 bits per component.
The problem becomes apparent when HDR is disabled to be able to play old PS4 games that do not have HDR support, then when the color reproduction of the console is displayed incorrectly, as seen in the image above. Although it has to be said that this has been taken from the title screen of Demon’s Souls, a PS5 game and not a PS4 game.
In the words of Alexander Battaglia of Digital Foundry:
PS5 currently does not play content that was originally on SDR correctly. Unfortunately, for backward compatibility, this can result in crackle of blacks and other changes when reproducing tone or color in games.
It is not as dramatic a problem as seen in the quoted tweet (Note, the images are the ones that accompany this section), but if you capture (content in) SDR and you compare it to the (content captured in) SDR in PS5 for the same game there are differences, which can be negative.
The correct color reproduction is part of the artistic section of a game, and it is expected that PS5 will be able to reproduce SDR content correctly, which are all games released in the early years of PlayStation 4, prior to the launch of PS4 Pro.
Is it a problem with a solution?
Both the PS5 and the Xbox Series use almost the same display controller in the SoC, the AMD standard, in order to send the video signal to the HDMI output. So how come the image quality is so uneven between the two consoles? The reason for this is in the HDMI controller, a chip that takes the signal sent by the SoC through the display controller.
SONY makes use of the Panasonic MN864739 HDMI control on PS5, which is currently capable of 32 Gbps, hence it does not comply with the HDMI 2.1 standard and works as an HDMI 2.0. In any case, this should not be a problem when it comes to reproducing the color in SDR correctly, since it requires less bandwidth than HDR.
The difference between HDR and SDR is simply allocating more bits per RGB component, 10 or 12 bits instead of 8 bits. So the SDR content should play smoothly. So it is very likely that we are facing a problem with the internal software of the console. So it is a problem that could be fixed in a future PS5 software update.