Taking photographs is all about capturing or recording light. Sometimes you can use the light around you and other times you will have to add light to the scene. The most common way of adding more light to the scene is by using a flash.
Depending on the type of camera that you have, you may have one or more settings for your flash. With the exception of the toy cameras, you will at least have the following options for flash: automatic, on, off, and "red-eye reduction".
In this section, we are only going to look at the flash that is built into your camera (called the built-in flash). For some cameras, it is also possible to buy a separate flash (called an external flash), which has some advantages. We will talk about that later in the advanced section. So for now, when we say "flash" we mean the flash that comes with your camera.
Flash On/ Off
Most cameras will let you choose whether you want the flash "always on" or "always off".
If you know that you will not have enough light to take a photograph, you can choose to always have the flash on. Just be a bit careful with this because there are a few problems with using the flash. The light it produces can be a bit harsh and also, because the flash is so close to the lens, the light casts no shadows that the camera can see. This can sometimes produce pictures with poor color and detail.
So, use your flash wisely, and experiment with having it on or off. If you can, try to get light from other sources, such as lamps.
If you are sure you have enough light and you do not want to risk having the flask off, then by all means set it to off.
Automatic flash mode
If the flash is set to automatic, then the camera will measure the amount of light when you take a picture. If the camera determines that there is too little light, the flash will be used automatically.
Almost every photographer has taken a photo where the eyes of the people in the picture ended up being red. This happens because the light from the flash is reflected from the back of the eyes causing a red reflection. To prevent this, you can use the red-eye reduction function if your camera has one.
Red eye reduction works by creating a bright burst of light. This light makes the pupil in the eye shrink. The pupil is the dark bit in the middle of your eye, which controls how much light enters the eye. The pupil gets bigger or smaller depending on how much light there is around you. The more light there is, the smaller your pupil becomes. Red eye reduction makes the pupil smaller so that it becomes harder for light to reflect back from the eye to the camera.
by Simon James Allanach, edited by Alan Frost
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