I once played this game on my cousin's PS2 and beat it but since it was so long ago these guides really helped in refreshing my memory and helping me get the achievements.
P.S. *spoiler alert, please don't read unless you've beat the game!!* Note: Your game WILL glitch and you WILL get stuck if you try this. If for some odd reason you want to try this, make sure you make a second file or wait till you beat it to start a new game.
I sadly had to do 2 playthroughs because of a glitch near the end of the game. It's when you find Pey'j and think he is dead. If you go back across the bridge instead of past the glass door, he'll be around. But since I forgot what to do I went to the hovercraft and had Pey'j stay near it, but when I went back to get the photo I wasn't able to go back up the elevator because the game thought Pey'j was still dead. Since I sadly saved AFTER all this and the photo, this f****d up my game so I had to make a new one.