60 is definitely playable, but its not ideal

[torok]

veritaz said:

Never played Killzone on PS2 but the Shadow of the Colossus HD collection on PS3 didn't have any bad framerate that I can remember. Did they fix it in the HD collection? 

Yes, they fixed the framerate on the HD collection. Killzone HD too, it runs at 60fps on PS3 while the original dipped to 20fps.