The light from even a small flash is as powerful as the sun but, given that it's only source of energy is a small battery, it can only produce this amount of light for an extremely small period of time - less than 1/1000th of a second. The actual length of time the flash fires for is very carefully controlled by your camera. During a flash exposure, your camera constantly monitors the amount of light reaching the image sensor and shuts off the flash as soon as the picture is exposed correctly.
It has to do this because the light from a small flash falls off dramatically the further away you are. In fact, it falls off with the square of the distance. That means if you moved your subject twice as far away, you would need four times as much light, 3 times further away requires 9 times the amount of light.
But you don't need to know that because your camera will do all that for you automatically. If you did move your subject 3 times further away the flash duration would simply be 9 times longer. This would still be an extremely short time and you probably wouldn't notice the difference. What you might notice is that the flash would take longer to recharge because it had used up so much power.
The very first flashguns were entirely manual and photographers had to do long calculations to determine the correct exposure when using flash. Studio flash units still work this way but most photographers now use flash meters to avoid having to do all this calculating.
So your flashgun will automatically compensate for the distance of your subject and give you a perfectly exposed picture every time - what could possibly go wrong?
Out of range
Although your flash will compensate for the subject's distance, it has its limits. It only has a certain amount of power and this translates into a maximum distance for your subject. If you try to take a flash picture from any further away, it will just be too dark or underexposed. Your camera's manual should tell you what the maximum subject distance is for flash photography is. In small cameras it is typically 12-15 feet.
It is often expressed as a range of distances rather than a single absolute figure because the conditions under which you are taking the photograph will have an effect on this maximum distance. For example, When you take a picture indoors the light from the flash not only goes directly to the subject but also lights up the whole room. The light that hits the walls and ceiling then bounces off them and adds to the light landing on your subject. Compare that situation with taking a flash picture outdoors at night. The light that doesn't reach your subject directly has nothing to bounce off, so overall, less light will land on your subject. Whilst your camera's flash might be able to compensate perfectly well for this, it will reduce the maximum distance for flash photography compared with taking pictures indoors.
Of course, indoors can mean a tiny room or an enormous one. So, if you are taking your photograph in a baronial banqueting hall with very dark walls and a high ceiling, you could be approaching the same situation as you have outdoors and the maximum distance for flash would be reduced.
What this means in practical terms is that if you have just taken a flash picture and it looks too dark, just get closer and try again. That will usually solve the problem.
Don't get too close
There is also a minimum distance for which you can successfully use flash. As your subject gets closer and closer, the flash duration gets shorter and shorter. Eventually, you will reach the limit of how quick the flash can be. In practical terms, this translates into a minimum distance for flash photography with your camera.
I'm sure all of you will have seen pictures of people taken with flash where their faces were bleached out and they look like ghosts. That's what happens if you get too close with a flash gun. Again, your camera's manual should give you the minimum flash distance for your particular camera.
If you can't find the information about maximum and minimum flash distances you could always do a few test shots and measure it for yourself. As a general guideline, if your subject is between 6 and 12 feet away, you should be all right.
Any digital camera has an array of functions and uses that enable the handler to take excellent pictures. However, many of the functions are not fully understood and the pictures are not of the best possible quality. Understanding these features enable the user to have complete control over their machine, and therefore get the best possible images.
Firstly the quality of the image that can be produced relies upon the resolution of the digital camera. This is made up of mega pixels. The number of mega pixels determines the level of detail in the picture. The pixels are the tiny dots of colour that make up image. These look fine on the computer or screen. However, once transferred to the computer and enlarged, images containing a lower number of pixels show these dots and so the image is flawed. Therefore, for good quality images the best digital camera to choose is one that has a high number of mega pixels.
The quality of the digital camera lens will also affect your picture quality. The lens should have a zoom feature, which enables you to zoom both in and out to create the perfect composition for your image. Each device will differ, but the concept is the same. The lens should be labeled with two zoom numbers; the smallest states the shortest possible zoom distance and the biggest number shows the longest possible distance. Consider the type of photographs that you are going to take when choosing your digital camera. If the pictures will mainly be indoors, then a lower number is required to be able to zoom out in enclosed areas.
The average digital camera will have an inbuilt auto focus function which will serve most amateur photographer`s needs. However, for more effects or for advanced photography, select a camera that has a manual focus option also. The auto focus can be turned off in some devices, which is an exceptional feature as the photographer can choose which option is best for the photograph being taken.
Another consideration is the shutter delay on the digital camera. The shutter delay affects the quality of focus and composition. The delay means that the picture is actually taken some time after the button is pressed on the camera. This means that the subject of the composition may have moved, clouds may shadow the expected lighting effects, or that your hand may shake and so the image is distorted and blurred. A good way to combat this is to only half press the button when you are composing the picture. This activates the auto focus and prepares the device for the shot. When the button is pressed, the photograph will be taken much more quickly, and will help combat any distortions.
Memory space is important if you want to take good photographs with your digital camera. Not only does this enable lots of storage, it also gives you the opportunity to take several photographs, in search of that one perfect shot.
Any digital camera will have inbuilt storage but this is minimal, averaging around 16 megabytes in total. The memory space can be added to with the use of a memory card or stick. The type chosen will depend upon what is compatible with your camera. Any memory card or stick is good, and they go up to 2GB in size. It is important that the type chosen is compatible with your home computer so that the images can be transferred and stored, giving you access to more photographic opportunities.
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