Here's a simple set up. Below is a white bowl with blackberries on top of a small countertop. There’s natural light source coming from the window behind the bowl and that's about it. I took a photo, shown in the first image, in Auto Mode. Too dark. At this point, most people give up and move on. But, wait! This scene can easily be properly exposed. It's only a matter of understanding the light and knowing how to use your equipment to get the proper exposure.
First, let’s talk about how light works, and why it is so important to photographers.