So Lost - Behind the Frame: The Finest Scenery (DLC achievement)
After a certain point in Scene 3 of the Jack DLC, you'll be forced to chase Amber outside. Once you've reached the coffee shop, "ghosts" of Amber will appear in certain spots around you, then slowly disappear. To get this achievement, make sure to look around and click on Amber whenever she appears before she fades away. I had to do it about eight times until it popped.