Of course one torpedo hit wasn't going to be notice by the crew, with the armor of the Yamato. Don't you forget that the battleship manage to resist the sea water and then fire from gamillon spaceships, and travel to space and destroy almost everything that was on it way...
I'm sorry but I couldn't resist to make a connection with Space Battleship Yamato...or Star Blazers.
The images are from the last movie made about the Yamato, "Yamato:Final Battle"?