How do I set the aperture on my SLR camera?
Step 2: determine the right aperture
Use the viewfinder to look at the subject you're taking a photograph of in order to determine the correct aperture. If you're making a portrait photo, select a wide aperture. You can recognize a wide aperture by its low aperture value. A landscape photo should be taken with a small aperture, which translates into a large number. The numbers usually range from 1 to 32. You can recognize aperture values by the letter 'f' that precedes it.
Step 3: turn the dial
Once you've found the correct aperture value for yourself, turn the dial that's located on top of the camera. For Canon cameras, this dial is often located on the front of the camera. For Nikon cameras, this dial is often located towards the back. Turn the dial left in order to increase the aperture, turn it to the right to decrease the aperture. Check the screen or the viewfinder to see whether you've selected the correct aperture.
Step 4: take the photo
Do you have a good view of the subject and have you correctly adjusted the aperture? It's time to take the picture! You can do this by pressing the shutter button, like you normally would when taking a photo.