In the downpour scenes showing the Rashomon Gate, Kurosawa found that the rain in the background simply wouldn't show up against the light gray backdrop. To solve this problem, the crew ended up tinting the rain by pouring black ink into the tank of the rain machine. The ink is clearly visible on the Woodcutter's face towards just before the rain stops.
This film is often given credit for the first time a camera was pointed directly at the sun. In Kurosawa's biography, he gives credit to his cinematographer for "inventing" it and himself for using it, but years later, during commentary that preceded the TV showing of the film, the head of the studio claimed credit, which Kurosawa bitterly denies.
During shooting, the cast approached Kurosawa en masse with the script and asked him, "What does it mean?" The answer Kurosawa gave at that time and also in his biography is that "Rashomon" is a reflection of life, and life does not always have clear meanings.
Often credited as the reason the Academy created the "Best Foreign Film" category.
In the wife's vision, the music used was only available during post-production. Kurosawa and his editor was amazed when they found that the music corresponded almost perfectly with the action on the screen, and thus they didn't need to change the scene to make it match the music.
The title "Rashomon" actually refers to the wraparound segments, from a Akutagawa story set at the Rashomon Gate of Kyoto. The actual story related in the film instead comes from another tale by Akutagawa, "In a Grove".
Kurosawa asked Toshirô Mifune to model his character's movements after wildlife, particularly the lion. Kurosawa's vision of how a lion was supposed to move was heavily influenced by the wildlife documentary work of husband-and-wife team Martin E. Johnson and Osa Johnson.
A very early use of the "hand held" camera technique (following characters closely through the woods).
Even during high noon the parts of the forest that the crew needed to shoot in were still too dark. Rather than use a regular foil reflector, which did not bounce enough light, Kurosawa and cinematographer Kazuo Miyagawa opted to use a full-length mirror "borrowed" from Daiei's costume department. The crew bounced light from the mirror through leaves and trees to soften it and make it look more like natural sunlight. Miyagawa later called it the most successful lighting effect he had ever done.
The title of the film has recently been added to the Oxford English Dictionary as describing "...resembling or suggestive of the film Rashomon, esp. in being characterized by multiple conflicting or differing ... interpretations."