An Intro to Lenses

Aperture
The aperture is the diameter of the lens opening. The larger the diameter of the aperture, the more light reaches the film or image sensor. The aperture also performs a critical function for focus. As the aperture decreases in size, the background and foreground gain sharpness. This zone of sharpness is called the depth of field.

Aperture is expressed as F-stop and will be indicated on your camera in abbreviations that look like this: F2.8 or f/2.8. The "F" stands for the focal length of your lens, and the number indicates the diameter of the iris opening.

Focal Length
16mm: An ultra wide lens, this bad boy distorts heavily, emphasizing objects in the foreground by making them look a lot larger than the background. Dynamic, but use with caution!

28mm: Standard for documentary and photojournalism to shoot cowboy shots, otherwise known as medium shots.

35mm: Another standard for documentary filming, also tight enough to shoot portraits.

50mm: Standard for cinema/video, it approximates the human eye's typical focal length.

85mm: A popular portrait, or "beauty" lens. Capable of making everyone look lovely!

200mm: The top of the scale for most people, this is a telephoto lens. Their inherent shallow depth of field makes them useful in eliminating unwanted foreground and background objects by simply throwing them out of focus. Great for sports photography!

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