Emacs as Finder/Explorer -- copy files

Question

I often want to copy files from one half (C-x 2) to the other of emacs, with different dired buffers in both halves.

The obvious way is to mark the files in one window, go to the other, move to the directory name, mark beginning, go to end, copy to the ring, return to the first half, and finally initiate the copy while pasting the name of the buffer from the ring.

Is there a shorter way to copy from one dired buffer to the other?

edit

Thanks, BRPocock. Under dired-dwim customization, I only see:

Answer 1

Under Customize Group: Dired you can use the Dired Dwim Target option to default to copying to the other dired window. (customize-apropos <Ret> dwim <Ret> should find it, as well)