This Seeking Tech article compares the Fidelity and Performance Pro graphical modes of Spider-Man: Miles Morales running on the PlayStation 5 Pro console.
You can find the comparison video below:
The Fidelity mode runs at a higher resolution with a frame rate of 30 fps. There should also be more pedestrians on the streets.
The Performance Pro mode runs at 60 frames per second. Although the resolution is lower, this mode uses PlayStation Spectral Super Resolution (PSSR) to improve image quality. However, there will be less pedestrians on the streets.
Both of these modes use the same ray-tracing features.