I take a lot of portrait photography and still life photography and I would love to have a way to figure out exactly what my depth of field will be for a given picture. Is there a way to find out this information?
To calculate depth of field, you'll need to know a few variables.
The first one is what make and model camera you'll be shooting with. Many of the depth of field calculators online ask you for this because they will automatically account for your sensor size and other things.
Second, you'll need to know the current focal length of your lens in millimeters because this makes difference when it comes to this calculation.
Third, you'll need to know your current aperture size (f-stop) setting and fourth, you'll need to measure the distance between your camera and your subject.
When you're all set, you can use one of the many depth of field calculators online or one of the available downloadable apps on your tablet or smart phone to find the actual depth of field for your situation. These calculators are very easy to use. One I can recommend can be found here.
Also, I recently wrote a post that covered much more on the topic of calculating depth of field, so if you'd like to read it, that may help some too.