Video at the bottom if you don't want to read.
Ok, there are TWO chances for you to get this achievement. I found out the hard way after restarting because I didn't snap the pictures in Episode 4. If you're in Episode 5, and forgot to take the pictures, DON"T QUIT. I've got a step by step guide for how you can get them in both Episodes.
Okay here goes: When you're at the end of Episode 4, after you tell Sayid what your name is you're going to go inside a building. As soon as you get down the stairs through the door, it will shut behind you locking you in. Fast forward about 10-15 minutes of play time, and you're in a room that's lit by blacklights.
As soon as you can control your character, go to the computer in the middle of the room. It's going to ask you to "enter the way home". Enter VIA DOMUS. If you're not sure why, read the compass, and it will tell you it is Latin for "the way home". Once this happens, the blacklights turn off and a countdown will begin. Go back into the computer and it will ask you about blacklights and blast doors. For the time being ignore that, and enter the same code you entered earlier to stop the countdown. 4 8 15 16 23 42. This will stop the countdown and give you an endless amount of time to screw around in the area. Now what you're going to do is go into the computer again, and select "d" for the blacklight menu. Instead of prompting you to change anything, you are taken into an IQ test. The answer to the first question is 63. The pattern is the numbers between are doubled, starting with 4. (4 8 16, then 32) The answer to the second question is L. (Every other letter).
Now that the quiz is out of the way, you will be taken to the blacklight menu. Turn on both blacklights again. Now back out of this and go snap a picture of the blast door with a glowing map. Tada! You got your first picture. Now, go into the computer and open up the door to the room with the lava lamp. (A or B,not C) If you opened the wrong door, just reshut it and pick the other door. There will be another map on the door in here, snap a picture of this one too. You can't get number 3 just yet, so don't bother looking for it. Once you've gotten all the tradeable items in here, just walk out into the hallway you first started in to end the episode.
Chapter 5: In case you didn't get the pictures on the way through Episode 4, you can still redeem yourself. After you do the memory game, Kate will let you out of your cell and give you a chance to snap the pictures again. You'll go to the computer and shut the blast doors, and turn on the blacklights. Then just follow the steps I gave you above. Once you have the pictures, you're done for now. Again, you'll have to wait until later to get the last picture.
Chapter 6: Play through the level until you find the computer that tells you communications are down with the mainland, and right after that start paying attention to your surroundings. You'll be looking for a wooden table with a map on it. If you get to a cutscene where your guy pulls a gun on a baddie, you went to far, hurry and reload your checkpoint before it autosaves. Snap a picture of the map on the table for number 3, and presto you have your achievement.