While shooting outdoors in earlier time the photographers use to keep the sun behind their shoulder which produces well lit photograph of the subject. In style results to be predictable but many a times it is very effective to have the sun or the light source behind the subject.
When the light source is kept at the back of the subject the outline of the subject is revealed very dramatically and this works very well on simple shapes. Color is much reduced further emphasizing the outline. While shooting with the camera pointed towards the light dramatic shadows and highlights form pleasing patterns of contrast adding energy and impact to the image. This form of composition or illumination is called backlight and along this comes some technical problem which need careful handling.
One of the tricky part is estimating the exposure. The extreme brightness range almost always exceeds the film’s latitude so that the photographer has to accept some loss of detail and because the incoming light produces brilliant highlight , the meter will indicate much less exposure than will actually be required. Most autoexposure systems can be overridden to give one or two stops extra exposure , so that some mid tone and shadow detail is recorded alternatively, a close-up reading can be taken off an important mid-tone area and the autoexposure system locked or set manually. Which ever way you estimate exposure, you must decide which of the highlight, mid-tone or shadow areas are most important, because loosing detail in one or more areas will create quite different moods in the picture.
If the colors and textures of the highlights are to be retained then much of the subject will be recorded in silhouette. But should you want to have the detail in the subject you will find instead that the rim-lit areas bleach out , creating a softer mood. With care it is also possible to reduce lighting contrast by using reflectors or weak flash to fill in the shadows. If you are using black and white film you can over expose slightly and then shorten the development of the film which will lower contrast.
Shooting into the light can also lead to problems with flare. Loss of contrast , reduced color saturation and diaphragm flare patterns can all combine to ruin an image. Good lens shading is the answer. When your lens hood is insufficiently deep you can often use your hand notebook or a piece of card to shied the lens from direct light. Sometimes it is possible to place the camera in a shadow throwby a convenient tree or part of a building.
shooting into the light is often thought of as simply a way of creating silhouettes. Attempting anything else can seem futile when almost all the subject detail is lost in deep shadow. The lack of direct light on the subject means that form and color are lost—and you have to rely on shape alone for identification. Despite this, backlighting does have other uses.
A backlit subject is not usually in darkness—it is lit by indirect light reflected from its surroundings. If you expose for the foreground, cropping as much bright background from the shot as possible, backlighting can be particularly good for portraits—giving a soft light without distracting shadows. Backlighting is also essential for showing the translucence and color of subjects such as stained glass and flower petals. If the light source is just out of the frame, or behind the subject, backlighting can become rim lighting—although the majority of the subject is in shade, its outline is caught by the light, creating a halo effect.