Customize Lock Screen When I lock my screen, sometimes it shows my iTunes library, other times it shows a screensaver, and other times it shows photos. 

I don't want it to do any of these things, I'd like it to just show a black background or maybe a picture.

Is there a way to customize it?
This is a system preference, and you change it in the Desktop &amp; Screensaver pane of... System Preferences.