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