First off, use the Tag Barrel to switch to Tiny Kong. As Tiny Kong, leave the level you are currently in and head into the water outside of DK Isle. Swim through the water over to the island with a pineapple shaped face on it. Once on this island, you will find a Tiny Barrel (near the back of the face), jump in to become small. While small, find an opening on the face and go inside. The queen Banana Fairy will tell you her sad story and grant you with the Banana Camera along with a new ability.