I have written many times about not using the flash for low light pictures, but today I will do a complete turn-around. Use the flash during the daytime! This procedure is called Fill-in-Flash, or Fill Flash.
Fill Flash is probably one of the best ways to give life and sparkle to “people” shots, but unfortunately is one of the least understood concepts in photography. In fact, many people are just so afraid of it they never try and condemn themselves to dark, featureless portraits or dreadful pictures full of bright highlights and disastrously dark shadows.
Let us look a little harder at why fill-in flash is required in the first place. Let’s start with taking shots in the bright Thailand sun at mid-day. It is all very well saying that you should take shots in the early morning or late afternoon, but many family gatherings are lunchtime affairs. End result, big black shadows where the eyes are supposed to be and an appearance of bags under the eyes you could put a change of clothes in.
The other time you are going to need a flash fill is when the light (generally the sun) is behind the person you are going to photograph. The camera sets the exposure for the bright background and the foreground then comes out so dark you will hardly recognize anyone’s face.
With both of these shots, what you need is a little burst of flash to fill in the shadows or the underexposed areas of the shot. Another side benefit is that there will be a bright “catch light” in the eyes, which makes the portrait much more alive.
With today’s automatic exposure cameras you must understand that it doesn’t know what it is that you are photographing. It doesn’t know that the person’s face in the picture is the most important item. All the camera brain can see is a mixture of bright lights and dark areas and it will give you an exposure to try and equalize these out. Unfortunately, in conditions of high contrast in the tropical sun, or back lit, the end result will be underexposure of the part of the photograph you want. It’s not the camera’s fault – it just means you have to get smarter!
Fortunately, these days many compacts and SLR’s do have the fill-in flash mode built in, but many of you do not use it – or even realize that you have this facility! Did you read the book that came with the camera? If you have it – then use it! Please do look, the shots you will get back will be much better than you were getting before.
Now, for those of you who have the whole kit and caboodle – an SLR with an off-camera flash, this last section is for you. The whole secret of fill-in flash revolves around flash synchronization speed. Some of the very latest, and expensive cameras will synchronize flash and shutter speed all the way through to 1/2000th of a second or better, but the average SLR will probably say that the synch speed is 1/125th or even only 1/60th and it is this figure which drives the exposure setting.
In practice, what you have to do is put the camera on shutter priority, let’s say the 1/125th synch speed and then read off what the resultant aperture setting is when metering the subject’s face. Let’s imagine the camera meter tells you that it will be f11. Now put the camera in manual mode and fix the shutter at 1/125th and the aperture at f11.
Next step is to set the power of the flash gun, measured in f stops. You do not want the flash to overpower the natural light, so you set the power to be one or two stops less than the aperture you have set in the camera. In the example, the camera is set on f11, so you set the flash on f8 for one stop or f5.6 for two stops.
Take the two shots at the different flash powers and decide which effect is best and practice with this technique for better photographs. You will not be disappointed.