Photo Terms with Pictures: By Alfredo Muskus/Tony Stark

Photo Terms

ISO-Film speed (the measure of a photographic film's sensitivity to light) is designated by a single, almost universally-accepted common system developed by the International Organization for Standardization which uses the initials “ISO” before the film-speed numbe.The ISO setting refers to the film speed of your camera.  Higher ISOs are used when it is darker outside and make the picture appear more grainly.  Lower ISOs are used when it is very sunny outside and are better quality pictures.  ISO's generally start at 100 and end at number around 6400.

Example: The following picture, taken of fast moving water was taken at an ISO Speed of 6400.

Depth of Field- The depth of field deals with the focus of the camera.  Pictures that are taken close up and have a very blurry background have a small depth of field, where landscape pictures generally have a wide depth of field, as the entire picture is usually in focus. Depth of field is controlled by the lens aperture, and extends for a distance in front of and behind the point on which the lens is focused. The higher the aperture, the whole picture is in focus. The lower the aperture, the background will be blurred. If you take pictures close, you’ll have a small depth of field. If you take pictures far away, you’ll have a large depth of field. Pictures taken with telephoto lenses have a small depth of field

Example: The follow picture was taken with a small depth of field

Light Meter- The light meter shows you how much light is being let into your camera and tells you if you need to change the shutter speed or the aperture.  The light meter helps you to make sure that the image you are taking a picture of has the right exposure. If you want your picture to be brighter, you change the light meter to + numbers. If you want your picture to be darker, you change the light meter to – numbers.

-Two different settings: one for pictures taken w/out flash, and another when using the flash The light meter can also give the perfect light for a good picture

Example: the following 2 pictures taken with the sun in front of me show the effect light meter can have. On jades image I lowered my light meter to -1.

 SPEED - A measure of the sensitivity to light of a photographic emulsion (combination). The shutter speed determines how long the shutter on the camera is open for and how much light it will let in.  This can range from 1/1000 of a second for bright days and multiple seconds for when it is dark outside.  When the shutter speed is longer than 1/30 of a second, it generally makes the image blurry unless you have a tripod or a flat surface.

Diaphragm- A ring or plate with a hole in the center that controls the amount of light entering the camera. An adjustable diaphragm in a lens controls the size of the hole, or aperture, thereby permitting more or less light to pass through the lens to the film. The Diaphragm of the camera is an opening that lets a certain amount of light into your camera.  The smaller the diaphragm, the less light is let into the camera.  Small diaphragms are used when it is bright, and larger ones are used when it is dark.  This also directly relates to aperture, as small diaphragms have large apertures and large diaphragms have small apertures.

Aperture- Relates to the diaphragm and controls how much light is let into the camera.  Small aperture=more light, large aperture=less light.

Kelvin Degrees- with Kelvin Degree you can change the setting based on what type of light you’re in. 5200 degrees is normal light. Tungsten light is 3200 degrees. The higher the degrees are, the bluer the picture is. All visible light has a certain Kelvin temperature that can be changed on a camera. The color of an image depends on the Kelvin Degrees of the light emitted from that object.  You can adjust the settings to change how the light in your photo looks, making it more blue yellow or red.

By: Alfredo Muskus- Fall 2010