How to Read the Aperture on My Canon

A Canon SLR allows the user to control the aperture.

Aperture is the size of the hole in the lens that allows light to pass through to the reflex mirror. Aperture is a feature on SLR digital cameras that can be manually controlled, unlike a point-and-shoot camera where the aperture cannot be adjusted. On your Canon, F-stop expresses the aperture. A small F-stop number means there is a large opening in the lens; a large F-stop number means there is a small opening in the lens that will not let much light pass through.

Instructions

AV Mode

1. Turn the mode dial, the large dial on the top-right of your Canon, to "AV." AV mode allows the user to control the aperture value.

2. Look on the screen on the back of your Canon. You will see the current "F(number)."

3. Move the small dial located behind the shutter button to adjust the aperture value. The F-stop number gets smaller or larger when you move the dial, and the changing F-stop is displayed on the screen.

Auto Mode

1. Turn the mode dial to the green square, or any mode featuring a symbol, such as portrait mode. Every mode is automatic, meaning that the camera automatically sets the aperture value, shutter speed, ISO and other settings.

2. Press the shutter button half way down and look through the view finder at the bottom portion of the black border. The second number from the left is the aperture value.

3. Press the shutter button half way down and look at the screen on the back of the camera. The F-stop number will be featured on the top right of the screen.

References

• Canon EOS Rebel Instruction Manual