Photography: Lighting devices

Photography is all about light. Our photographs are recorded light. How we control the available light and add additional light when needed is basis for all photography. There are numerous controls and methods for controlling light available to today's photographer.
Light Meter: Your camera's light meter is your link to understanding how your camera sees light. This device takes into account all of the settings on your camera (aperture, shutter speed, film speed, etc) and tells you what type of exposure that combination plus the available light will create on film/sensor. The first step to understanding photography lighting is to understand this tool for measuring light.
A light meter is an instrument inside your camera that tells you if the amount of light reaching the film will be enough or too much to properly expose your image. The light meter takes into account your shutter speed, film speed, and aperture settings.

Aperture: Now that you know how to read your light meter, you need to understand how the different settings on your camera affect the light itself. Aperture is an adjustable opening inside your camera lens that adjusts the amount of light that can travel through the lens. Aperture is used in conjunction with other settings to control the maximum amount of light that can reach the film/sensor.
Aperture is one of the most confusing aspects of photography for new photographers (and some old hands). In truth, it does not have to be a confusing. The aperture is an adjustable opening inside the camera lens that works very similar the iris in your eye.
When the aperture opens wide (like your eye dilating), more light is allowed through the lens to expose the film. When the aperture is narrow (like your pupil in bright light), less light reaches the film. This works in conjunction with shutter speed and film speed to determine the total amount of light that reaches the film. Aperture size also affects depth of field.
Shutter speed: Shutter speed is another control used to modify the amount of light that reaches the film/sensor. Shutter speed controls the amount of time the film/sensor is exposed to light. In addition to controlling light, theshutter speed also has the greatest effect on how motion is represented in the image.
Shutter speed one of the 3 basic light control functions of a camera. Aperture, film speed, and shutter speed work together to adjust how much light strikes film and how that light is recorded. This lesson will explain in detail what shutter speed is and how it relates to photography.
One of the most requested photography tips is shutter speed help. Shutter speed is one of the most basic important controls on a camera. Shutter speed controls the amount of time that your film, or digital sensor, is exposed to light. In effect, the shutter determines what image is captured on your film. The shutter is a small plastic sheet that opens and closes to allow light onto the film or prevent light from reaching the film. The shutter is opened when you press the shutter release button on your camera to take a picture. The shutter speed determines how long the shutter remains open.

In cameras with TTL (through the lens) viewfinders, the shutter release button also moves a mirror out of the way of the film and shutter curtain. It is this movement of the shutter curtain and the mirror that gives taking a picture its distinctive "click" sound. As you become more familiar with your camera and shutter speed you will begin to notice the difference in the sound of the the "click" based on the speed of the shutter. In time, you will be able to tell approximately what shutter speed any camera in the room is using just by the sound of the shutter.
Once you understand what each of these items are, it is time to pull them together to create a properly exposed image. It does bear noting that "properly exposed" refers to the exposure the photographer intended. Sometimes the photographer wants to underexpose and image or overexpose it. Proper exposure depends on the intentions of the photographer.
Proper exposure is created by using various combinations of film speed, shutter speed, and aperture. The photographer then checks the light meter to confirm that these combinations will result in the desired light reaching the film or sensor.
Film speed is almost always the first factor that is determined. With film cameras, the film speed is determined by what film you use. In a digital camera, the camera or photographer chooses a film speed equivalent to use in a given situation. The chosen film speed tells the light meter how much light the film requires to create an image.
After a film speed is chosen, the photographer considers the subject and environment of the photograph in order to determine if depth of field (controlled by aperture) or motion control (controlled by shutter speed) is more important to the image. Occasionally there are subjects where both motion control and depth of field are equally important, or the dominant concern can chage quickly.