Rocksteady Studios has released a minor update for Batman Arkham City patching it to version 1.03. This appears to deal with some PS5 compatibility issues.
Just like some of the backward compatible games including Joe’s Diner and Dynasty Warriors 8, Batman Arkham City was updated to add support for PS5. The patch notes don’t explicitly mention what issues were occurring on the PS5 that forced the developers to release this update, but it doesn’t appear to deal with enhancing the game with PS5 support.
As for the details on what is fixed, the only thing that has been patched with this update is a rare bug that was affecting the game when running on the PS5.
As far as we can tell, the game was actually rendering at a lower resolution on the PS5. This was due to a bug that led to the resolution dropping from 1080p on the PS4 and PS4 Pro, to dynamic sub-1080p on the PS5. As a result, the game looked blurrier, and to top it off, it was still locked at 30 FPS on the PS5.
The new patch should have resolved the issue with the resolution getting downgraded on the PS5, but don’t expect to see the game running at a higher frame rate with this patch.
Batman Arkham City was released on the PS4 as part of a Batman Arkham Collection that included the first two games in the series that were remastered for a higher resolution and textures. It was also possible to play the game at a higher frame rate if you opted to removed any of the post-launch updates, or owned a physical copy of the game.