Beginners Guide To Off Camera Flash
Beginners guide to off-camera flash
Why off-camera flash?
- You can shoot at any time of the day or night, and control your lighting conditions. This means you can take great photos at mid-day on a bright sunny day, after the sun goes down and on a dark, overcast day.
- Flash makes colours pop or eliminates unwanted colour casts.
- You can control where and how much light hits your subject.
- You have control over ambient exposure. Like the sky and the light on your backlit subjects, or the night lights in the distance and your subject in the foreground.
- You can put the light behind your subject for dramatic effects.
You will need:
- A compatible flash or two with a rotating head and both TTL (through the lens) and manual abilities
- A wireless trigger and receiver set. This is how your camera communicates with your flash. The transmitter mounts onto the hot shoe of your camera, the receiver attaches to your flash.
- A tripod or lightstand. A lightstand is ideal because you can add light modifiers like an umbrella, or soft box. Whichever way you decide, the sturdier the better.
What is TTL?
This is where you let the camera decide how much light the flash is to emit. TTL (Through the Lens) is when your flash sends out a pre-flash to assess the scene. This tells the flash how much light it needs to flash to make a good exposure. TTL is good to use when your subject is moving quickly and distance or lighting conditions are changing. You can still make adjustments to the flash exposure in TTL, you would use exposure compensation on your flash like you would on you camera, by adjusting the amount of light by +/- 1/3 stop increments.
Why use Manual?
In Manual, you get to decide how much light your flash emits. Sometimes the lighting in a scene might be a bit 'confusing' for a flash in TTL mode. Like maybe sunlight is lighting half a room but you want to expose for the entire space. Or maybe you want to let ambient light in as well as light up your subject. So in Manual mode, you can turn the 'power' up or down for more control over the amount of light added to your scene.
In Manual mode you can control the zoom, or how wide the flash's beam of light is. In TTL mode, your camera will read the zoom on your lens and automatically set your zoom on your flash. If you need wider coverage you would use manual mode to change the zoom to a wider setting. The effect of the size of the beam is kind of like a hose head with an adjustable stream. A wider setting sprays the light and it lands closer to you, whereas a narrower beam of light is like the 'jet' setting. It hits a narrower area and goes further.
Set up your camera
- Shutter speed. Every camera has a 'sync speed'. A common maximum sync speed is 1/250 of a second. In this case the camera's shutter speed must be 1/250 or less. Otherwise the bottom part of your image will not be lit at all, and you'll get a big black line in your photo. A slower shutter speed will let more ambient light in.
- Aperture. This controls how much flash will light your scene. The lower the number, the more more power you get. If your flash is too bright, raise the aperture number.
- ISO. This is another way to control the amount of light from your camera. Increase ISO for more flash, decrease it to turn the light down.