This achievement is earned for finding optional photo #8. If missed on the first run, you can "Play Episodes" and select specific parts of the Episode in order to find the missing optional photos through collectibles mode. The following collectible is described and can be seen below:
] - Optional Photo #8
Once reaching the diner area, talk to the guy smoking out front until he mentions his 1977 Truck. After that rewind, and talk to him again choosing the new 1977 Truck topic of conversation and then choosing Rachel Amber
. After that, he will allow you to take a picture of this truck across the street. Do so.
Collecting all 10 photos will also reward you with the following achievement: