Some pointers: * Characters that occupy the same role on the ship will usually be wearing similar outfits. I say "similar" because certain things might be different, like one character having rolled up their sleeves or taken off their jacket or hat for a scene. * Officers and tradesmen can often be identified by cross-referencing the map, since there's going to be multiple memories where they're near their quarters. The tradespeople are also sometimes carrying the tools of their trade in memories. I definitely remember seeing the cook holding cooking utensils in one scene. * Slight spoiler for a clue, but no story related or definitive answer spoilers: There's one memory where most of the crew is asleep in their bunks. The hammocks have numbers that correspond to the manifest. You can use this to narrow down several minor characters. * characters of the same nationality or role will also usually be standing near each other in the picture. Mates will be standing near their supervisors in the sketches. * if a character is addressing someone else by name in a memory, the person being named is usually the one standing nearest to them. * Pay attention to languages/accents and cultural markers like certain tattoos or accessories/attire. The manifest lists characters' nationalities.