Let`s Talk about, “Exposure” | Part I
Most cameras today automatically detect and attempt to compensate for ambient light in an area. The auto-system will try to strike a balance with the present light, for the most part they’re successful and the result will be acceptable. One situation that can give it trouble though, is having the sun behind your subject. Your meter will likely read the abundant light and recommend cutting it down. Say your subject is a couple of people with the sun just behind them. If you cut the light down too much, it may render them mere silhouettes. So you have to know when to override it.
Film requires a very specific amount of light in order to function properly. Unfortunately for you, the light around us varies tremendously. As an example, an area outside on a clear and sunny day may be hundreds of times brighter than one just a few feet indoors. You must know how to adjust your aperture and shutter settings so your film gets just the right amount of light it needs.
Controlling the light entering your camera is simple enough, each time you adjust the aperture or shutter settings one full step, it either halves or doubles the original setting. If you balance an increase in shutter speed with a decrease in the aperture size the total amount of light entering the camera will remain the same, allowing you to deal with different situations and still get the same exposure.
This doesn’t mean the different settings will render the same final picture, though. In bright light conditions, you’ll have a much wider field of settings to choose from, but dim light will restrict your options some, often forcing you to use a wider aperture or slower shutter than may be ideal. So, many times you’ll have to make a compromise in some way or other.
As mentioned previously, most cameras have some form of measuring the available light. Many use external, light-sensitive cells to measure the light, then look at the film speed you have set and either recommend or automatically make an adjustment. Some cameras make use of internal light-sensitive cells that meter the light coming through the lens itself. Either way, when you trigger the meter, a display in the viewfinder shows what settings to use. The display may be the actual settings, a needle indicator, or even a small light.
The exposure the meters will aim for is a mid-tone, intended to provide maximum detail and be suitable for most subjects. Most of the time, your subject will have a variety of shadows and highlights, with only a few mid-tone areas. How this is handled varies from meter to meter, as some try to average out the exposure, others weight it toward what’s usually the more important areas of the image, the center and lower half. Some meters read a particular small spot, allowing you to more fully control which area gets the most attention.
You can also acquire hand-held meters, which allow you to be very specific when taking readings. Most hand-meters use a dial which displays the recommended aperture and shutter settings.
Regardless of what kind of meter you use, you need to understand how it works and how it reacts to certain situations, so you can take appropriate action depending on what you want.
Manual and Automatic Options
There are important differences between the settings manual and automatic on through-the-lens metering cameras, and there are three automatic settings. These are aperture priority, shutter priority, and fully automatic. You’ll find that most cameras give you at least two options, usually a priority mode and manual. Fully automatic cameras are easy to use, but have one major drawback: the computer sets the aperture and shutter itself, not allowing you to make changes. They are thus not suitable for a particularly creative picture. With a priority camera, you set one or the other, depending on which priority mode you’re using, and the camera sets the other. It frees you from some of the load, but still gives you a great deal of control.
Controlling the f-number
Aperture priority allows you to set the f-number personally, giving you control over depth-of-field. Shutter priority gives you control over the shutter speed so you can set it for moving objects. Either way, you control both settings. By adjusting one setting, you are indirectly adjusting the other, so simply adjust the one until the other is where you want it. Manual allows you to directly control both aperture and shutter settings and you can overide the meter. This gives you a great deal of control, which is particularly useful in unusual lighting conditions or when you want a specific effect. Even if you don’t use it a great deal, a manual setting is a must because you will need it from time to time.
Please Watch this Amazing Training Video