Here is the full list of all 22 Martha Is Dead achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Taken a photo with every camera accessory
Discovered the house in the woods
Completed the games story
Completed all telephone calls for obtaining information
Played the second puppet theatre sequence
Completed Lapo's quest
Played the first puppet theatre sequence
Entered the family crypt
Every newspaper edition read
All diary pages read
Carried out a divination every day
Communicated with the White Lady
Developed 10 photos with no story link
Collected all camera accessories
Fixed the bike
Developed the first photo
Taken 5 photos with no story link
Taken the first photo
Dressed in Martha's clothes
Observed an in-house object
Taken all IR photos with hidden riddles
Taken all 4 IR photos of the lady