Mission 4 Chapter 1
As you start the chapter look turn around and look at the large green door, just above you will see a broken ledge, back up and you will see the target hidden behind it.
Follow the wall on your left hand side, just as you exit this first little enclose area you will see a "Pure" sign above you on the left, the poster is located next a door just below this sign.
From Poster 1 look straight ahead and up. You should see a washing line and several other objects on the roof. Look to the left side of the building and you will see an air duct with the next target.
Enter the underpass and follow it until you get to the second set of stairs leading out. The poster will be on your right hand side as you approach the stairs.
Exit the underpass and follow the buildings on the right. You should see a "Redback Oil Pipeline Construction" sign. Just after this sign you will see several enemies exit a garage door, once you have killed them all enter the garage door and you will see the poster next to a payphone.
Climb up to the next level and head through the door to your left. Once you get to the large wooden planks you will see the target in front of you on the side of the building ahead.
Continue forward to the next shutter you need to lift. You will see two jets fly over. if you look ahead and to the right you will see the poster on the right hand side on top of a small building.
From Poster 4 turn around and look back towards where you entered the area. You will see the target above the shutter on the wall.
Head down the stairs and break through the wall. Follow the path until you come to the second breakable wall. Walk up the stairs and turn around half way up. You will see the target high up on the wall.
Keep following the path until you get to the final shutter. Before lifting it look directly to your right as you enter the room. The poster will be on the wall above several special ammo crates.