How do you beat the mission when you take pictures of metal gear in sons of liberty

If you are talking the mission last area (hold no.3) well you simply have to aim the CAMERA at Metal Gear from the front (behind the marines) from the right (behind a container on the right) and from the left (behind a container on the left). You also have to take a photo of the MARINE lettering which is located either on the far right end of metal gear or on the opposite side. Once you have all four, go to the computer (located on the south-east side of the room) and press the action button in front of it.