FAQ About Camera Flashes
Camera flashes are an important part of a photographer's arsenal of accessories. These versatile devices serve a number of different purposes, well beyond simply providing a scene with more light. It's no wonder, then, that there's such a wide range of flashes out there to choose from. While having a variety is nice, it can make the decision-making process a little daunting. Read on for the answers to some of the most commonly asked questions about camera flashes to help guide you in the right direction.
Why do I need a camera flash?
It goes without saying that camera flashes are used to illuminate scenes with low-light conditions; but there's a lot more to them than that. Flashes can help bring about more balanced exposures in daylight conditions, create dramatic lighting effects, or freeze and illuminate moving subjects. They're also useful for providing more light when you're using a small aperture to increase the depth of field.
What's more, you can mix flash light with ambient exposure to emphasize certain objects or subjects in a scene and produce some impressive creative effects. Contrary to built-in flashes, on-camera flashes allow photographers to dictate where the light is sent and bounce the flash light off other surfaces. The result? More natural photos and minimized undesirable effects like red eye.
What should I look for when buying a camera flash?
You'll notice pretty quickly there's a ton of features when it comes to camera flashes. Here are a few main ones to focus on.
Guide number
The guide number represents the maximum amount of illumination a flash can produce. The higher the guide number, the more powerful the flash. It's the product of multiplying the f/stop of an exposure with the distance to the subject. You'll need to know the guide number so you can set the aperture correctly and get the proper exposure.
Sync speed
Sync speed is all about the relationship between the flash and the shutter. It's the fastest shutter speed you can use with flash. Sync speed is important as it allows you to shoot at larger apertures, thus requiring less power, which in turn speeds up the recycling rate and allows you to shoot more frames per second.
TTL flash metering
TTL (through-the-lens) flash metering is the standard method for determining the proper flash exposure. The moment the shutter button is pressed, the flash emits a burst of light that hits the subject and reflects back through the lens. The returning light is then put through an exposure meter to calculate the appropriate flash power that'll ensure the optimal exposure for a given scene.
What other things should I consider?
Along with checking out the above features, it's important to determine exactly what your needs are so you can make the best possible decision within your budget. Another important thing to keep in mind is, of course, compatibility. It's generally recommended to get a flash that's best suited to the type of camera you use, either by sticking with the same brand or buying a flash from a compatible third-party manufacturer. Also consider build quality and whether or not it will stand up to the typical conditions you work in. For example, if you're outside a lot, you might want to opt for a flash with a full-weather sealing.