I have a darkroom in my apartment, and my walls are covered with photographs I've taken. I'm ashamed to admit it, but I leave my camera on the full auto settings the majority of the time and get pretty good photos. Professional photographers have to know the difference between f-stops and shutter speeds, but I've just never taken the time to learn. However, I've always known that an in-depth understanding of the physics involved in photography is needed to take those breathtaking images that I see on Flickr.

Via Nigel, I see that photography tutorial tip site Photonhead has a virtual camera that lets you play with advanced camera settings and see what the resulting photograph would look like. These SIMCAM demonstrators are great for visualizing the differences between two settings, and will help relate numbers on a dial to a mental picture of what happens in the field. There's a SIMCAM for shutter speed and aperture (f-stop), a film speed simulator, and one to show the severity of camera shake under different settings.