The Aperture Ring is the rotating ring on the lens barrel that controls the selection of f-stops. The aperture ring is where you will find the minimum and maximum f-stop settings for a given lens, and the critical focus mark.

This is the jargon or informal name for digital artifacts found in raster images. These star-line lines appear where there should be a smooth straight line or curve. Jaggies appear when the output device (i.e. printer or monitor) doesn’t have the adequate resolution to reproduce a smooth line.

This is a hybrid auto-focus mode available on the higher end Canon EOS digital cameras (i.e. 5D, 1000D, etc.), where the camera automatically switches between One Shot mode and AI Servo mode (AI refers to “artificial intelligence”). AI Focus AF initially begins in One Shot Mode, and when the camera's AF sensor detects that the main object is m [..]

AI Servo AF is an auto-focus mode that continuously focuses on a subject –one that is moving -- until you find that decisive moment to snap the picture. The AI in the title refers to “artificial intelligence” and the camera's computer makes a prediction on where the subject will be.

AE Lock is a camera setting that lets you lock your automatic exposure, so you keep the same combination of f-stop and shutter speed, when your camera is in one of semi- or full automatic exposure modes. In addition, AE Lock holds the exposure settings over a series of pictures, such that the camera isn't recalculating the exposure after each [..]

Ambient light is the unadulterated and unassisted light in any environment. It may be the sunlight, it maybe the lamps in your apartment, plus the sunlight, it might be the light from neon signs, street lights and moonlight at night.

Angle of incidence is a technical term that describes the angle of light as it strikes a surface. Understanding the angle of incidence is important when setting reflectors and determining what the angle of reflection is going to be, as they are one and the same.

The Angle of View is the width of a subject as seen through a lens. It is typically stated in relation to the diagonal length of an image. A larger angle of view (on wide angle lenses) shows the viewer more things and space, but they appear smaller. Conversely, a small angle of view (on telephoto lenses) shows the viewer less things and space, but [..]

The aperture is the opening in the lens through which the light travels to hit the image sensor (or film frame). The aperture controls the amount of light that hits the image sensor and determines that conical angle of light rays that come to a focus point on the image plane.

Aperture Priority is a semi-automatic setting for your camera, in which you manually set the aperture (or f-stop) and the camera's computer determines exposure by selecting the shutter speed that works best for the selected f-stop. Aperture Priority mode gives you greater control over an image's depth of field in an automatic mode.