Thanks Dodgy! I researched some photos in a Time Life book on war in the North Atlantic and via some internet U-Boat history groups on the type VII-C. Whether or not what I did is 100% correct I really couldn’t say. I used a bit of grey wash to the decking so the “wood” color wasn’t so pronounced. Artistic license would probably be the answer. I think it added a subtle constrast to the rest of the sub.
That is a fantastic diorama. I am building a water base for a group build right now and can only hope my water looks half as good as yours. The way it is slopping up over the sides of the deck like that is just spectacular. The seas look perfectly rough. Tremendous job here.