Taking good flash photos in low light is challenging. After all, you’re often using only one rather harsh light source, coming from a single point not very far from the camera lens. Your photos will look almost as if you’d fastened a flashlight to the side of your head, or somewhat like you were wearing a miner’s helmet.
If you own a DSLR, and if you want to take consistent flash pictures, the first thing you’ll need to do is purchase a separate flash unit. The small integrated flash head that comes with many DSLRs is useful if you absolutely need to get a picture and can’t get along without it, but it has severe limits.
It’s not a question of power. In some cases, the small unit on your camera would be powerful enough. It’s more a matter of flexibility.
A good external flash unit with a tilt and flex head is a smart first step, because it can be used to bounce the light around. Combine this type of flash with the proper accessories and you can produce various lighting effects that will be a great tool for making better pictures. Ask around your local camera shop and have a look at products designed to alter, diffuse, and reflect light from a flashgun: there are several types and various brands to consider. Gary Fong products and other similar lines are a great starting point.
When purchasing your flash unit, make sure it offers full compatibility with your camera. In-camera controls of flash lighting are increasingly complex and allow you a great deal of creative tools. Just make sure all your gear will work together.
In our example, the first shot of the vintage camera is blurred due to a very slow shutter speed because of weak lighting. We then made a first flash photo with the camera’s pop-up flash. The lighting is better, but there are harsh shadows behind the subject. The third shot was taken by bouncing the external flash off the ceiling: no more shadows but a lot more contrast. Finally, we used a light diffuser for the fourth shot. We have almost no shadows behind the camera and much better shadow detail in front. All flash exposures were taken in TTL mode.
Don’t fear using TTL for your flash exposures. Unless you’re shooting hyper-critical photos, the automatic exposure will get you close enough for most purposes. When using TTL, your flash gets instant feedback from your image sensor and makes the correct exposure (see diagram).
Unless you are using sophisticated studio lighting and precision flash meters, TTL is your best friend. In addition, most DSLRs allow you to apply your own exposure correction.
With your camera doing the exposure calculations, you can concentrate on what really counts: making sure the light looks right, and adding whatever reflection, diffusion or other adjustments are required.
Some photographers prefer to live dangerously and assume they will always find a nice bright surface to bounce light off, but it’s safer to take nothing for granted and make sure you have your own reflectors and diffusers. You never know when a red ceiling or a red wall will creep up on you and leave you dealing with a pink wedding dress ...that’s not really pink!
Using flash also means making sure your subjects don’t look straight into the light, because red-eye is a real issue and an iffy correction at best.
So get out there with a proper flash, observe and learn how light behaves, and don’t be afraid of relying on auto TTL.
As far as that little pop-up flash on top of your camera, dont take it too lightly. It can, and will, get useful outoors for fill light. But that’s another column!