screenshots posted on many video game sites recently show a scene
deleted from the film which makes it to the video game: Cornelius
and Caspian discussing Old Narnia while out to stargaze.
Caspian seems to wear the same shirt that he later
wears with his Farewell Outfit;
or it's possibly a different shirt with a similar cut. It's quite
impossible to match the colors from the lighting, but the pintucks
stitched the differing ways on the collar matches exactly.
He also looks to be wearing his plum cloak tossed over
his shoulders, which he also wears later when escaping the castle.