Camera Basics: Here’s How to Use the Depth of Field Preview Button on Your DSLR (VIDEO)

What the heck is a depth of field (DOF) preview button? It’s that little button adjacent to your camera’s lens mount that you’ve never used because you don’t know what it does. Believe it or not, the DOF preview button is there for a reason, so watch the video below and make it your friend.

Typically when shooting with a DSLR (or film SLR camera) the diaphragm of your lens remains wide open until the moment you snap the shutter, at which point it stops down to the aperture setting you chose. That’s so the image in the viewfinder is as bright as possible while you’re framing your shot.

But if you press the DOF preview button before taking a photo the lens will immediately close down to the f/stop you’ve chosen, thereby enabling you to “preview” the depth of field that will result from the aperture setting in use. This was a more common technique in the days of 35mm photography, but it’s equally helpful with modern digital cameras.

The one caveat here is that the image in the viewfinder will appear darker than normal with the DOF preview button depressed (unless you’re shooting at maximum aperture). Therefore, when using this approach with a DSLR it’s best to shoot in Live View so you can see the results more clearly with the LCD on the back of your camera.

You can find more shooting tips on the ZY Productions YouTube channel. And if you missed yesterday’s primer on how shutter speeds work, be sure to take a look.

Via PetaPixel

Mcgrele's picture

Terrific. I had not fully understood the value of this button before. Thank you.