Get the camera.
On disc1 when you go for the spg-1 go to the bottom where you fight the 1st boss go to the bottom and tap on the wall it will sound hollow.
Use the c4 on it and it will blow a howl in the wall the will be 2 doors one will be level 5 and one will be level 6 the on level 5 door is the one with camera.
We have more cheats and tips for this game here, Metal Gear Solid cheats
Comments for this hint