Digital Foundry carried out a thorough test on the PS1 PS2 and PSP games in backwards compatibility offered on PS4 and PS5 through the new subscription PS Plus Premium with results that they are not satisfactoryalso in this case.
We had already seen a certain rejection by ElAnalistaDeBits as well, but in this case the analysis is much more in-depth, as usual for Digital Foundry. In any case, according to the British column, the backward compatibility of PS5 and PS4 “is not good enough”. The good news is that the PS1 emulator used is not the same as the one present in the infamous PlayStation Classic and is more advanced, but it shares a wide range of problems with it.
As for the problem of 50 Hz PAL Also used on NTSC games, Digital Foundry argues that the solution isn’t common to all games, but for most it is. Oddly enough, Sony’s first parties are all running at 50Hz at the moment. As for Ape Escape, for example, curiously it has the cutscenes at 30 fps, with various frame pacing problems, while the gameplay is in fact at 25 fps.
The continuous stutter and frame-rate inconsistency derives from the need to display a 50 Hz code in a 60 Hz container provided for PS5, but the situation does not improve even by selecting 50 Hz as the console output, since the general slowdown is still evident. Even Wild Arms, Jumping Flash, Kurushi, the two Worms and Everybody’s Golf are all only available in PAL version at 50 Hz, despite being the Asian lineup of PS Plus, while curiously Tekken 2 and Mr Driller go to 60 Hz and they look much better.
As for the resolution, on PS5 classic games undergo an upscale to 192×1440, which results in much more defined polygons and textures, but according to Digital Foundry there are problems in terms of sub-pixel accuracy, related to the lack of precision in floating point operations. The result is a certain inconsistency that is typical of PS1 games, with unstable 3D models having an effect perhaps even worse with the increased resolution.
The options for i filters are unconvincing, compared to other emulators or dedicated retrogaming machines: Default and Modern are very similar, with the latter increasing the contrast resulting in a darker image, while the Retro Classic option introduces a scanline filter that has it looks good, even if it doesn’t line up perfectly with the effective pixel grid, which makes it much more crude than dedicated solutions seen for example in the RetroTink 5x Pro.
The options foraspect ratio raise doubts: the default option with simple 4: 3 inserted in a 16: 9 window works fine, but the other options (1: 1 and Square pixel) introduce distortions, squashing the image with incorrect scaling . According to the heading, these options appear to have been included without understanding precisely the effect they should have had.
As for the PSP emulation, this one doesn’t have the 50 Hz problem, of course, but it does have others. In particular, as the resolution is increased from the original 480×272 to 1080p, the 2D elements appear filtered and blurred. Also, strangely enough, PSP has the same filters as PS1 including scanlines, which is quite bizarre considering that the original console had an LCD screen and not a CRT, so those lines don’t make sense. The aspect ratio options taken from PS1 also don’t add up, considering the original screen was already 16: 9.
As for the PS2 emulation, finally, it is basically the same seen for the PS2 Classic on PS5, with the resolution increased and some problems remained unchanged from the emulation seen previously.