Table of Contents

• Flash Exposure
• Light Fall-off
• On-Camera and Off-Camera Lighting
• Types of Lights
• Light Modifiers

Flash Exposure

When a photographer introduces his own light sources into a scene, exposure moves beyond the in-camera settings for ambient light. The strength of each light source can be individually adjusted, creating a separate exposure for each light.

Start off by considering the simplest scenario: a single light setup. In this situation there are two exposures that need to be configured:

1. The camera’s exposure, i.e. aperture, shutter speed and ISO.
2. The flash’s exposure, i.e. power level.

Being able to adjust each individual light source makes it possible to be extremely creative, for the photographer to design any lighting setup imaginable.

One of the easiest ways to begin picturing flash exposure in your mind is think of the classic “sunset photo”. You’re in a tropical location with a loved one and the sun hits the horizon, so you throw your arms around each other and ask someone to snap a photo. If there were no flash on the camera, the photo would turn out one of two ways:

1. The sunset would be properly exposed, but you would appear as a silhouette.
2. You would be properly exposed, but the background would be blown out and entirely too bright.

Using a flash solves this problem. The camera exposure is set for the ambient light in order to properly capture the sunset, which has the side-effect of turning you into a silhouette. But now the flash comes into play — the flash intensity is adjusted to light you up. Now you have a nice looking sunset as a backdrop (exposure A) and you, nicely lit up in the foreground by the flash (exposure B).

Light Fall-off

Flash exposure settings are calculated based on the distance to the subject because light falls off over distance. Quite simply the farther away your subject is, the more light you need to get a good exposure.

Imagine taking a photo of two people with a single light setup: your camera, and the flash stuck on top. One person is standing twice as far away from your as the other. You make your settings based on what your camera tells you is the right exposure for the person in front. In the resulting photo the person in front will be properly lit, but the person standing in the background will be underexposed because the light became less intense as it traveled over that distance. Conversely if you made your settings based on the meter reading for the person in the background, the foreground subject would be overexposed.

Light fall-off is calculated with the inverse square law.

On-Camera and Off-Camera Lighting

There are two places to put your lights: on-camera or off-camera. An on-camera light is physically attached to your camera… it’s the built-in flash, the pop-up flash, or the flash unit sitting in the hot shoe on top of your camera body.

On-camera lights sometimes get a bad rap because they are most often associated with flat, washed-out images. A tiny little flash pointed straight ahead and left on auto mode often lights up the subject, but doesn’t do anybody any favors. But if you can control your on-camera flash’s settings and power level, and especially if you can point the flash head in a direction other than straight ahead, there is a lot of room for creativity.

With off-camera lighting the photographer is free to place his or her light sources almost anywhere. By using multiple lights in different positions, with all sorts of different settings, configurations and modifications, the photographer can put together near limitless creative lighting schemes ranging from simple to extremely complex.

Off-camera lights need a way to be triggered when the photographer hits the shutter. A PC cord can be used to wire the lights to the camera, or one of many wireless methods can be used. This is often done optically, via infrared signal, or with with radio wave transmitters.

Types of Lights

We can put photographic lights into two categories: small lights and big lights.

Small lights are often referred to as strobes or speedlights (Speedlight and Speedlite are trade names used by Nikon and Canon). These flash units are lightweight and portable. They can put out enough power to light groups of people, illuminate reception halls and whatnot.

Two small flashes. Photo: Churl Han.

Big lights are what you often find in studios and on commercial shoots. These lights are much more powerful and have a larger light source. They’re powered via a battery pack or outlet.

Alien Bees 800 strobe with a shoot through umbrella. Photo: Andrew Iverson.

Light Modifiers

Photographers use all sorts of contraptions to modify the behavior of their lights and achieve all sorts of pleasing results.

The goal of many light modifiers is to make the light source larger which results in a “softer” light with more pleasing shadows. Direct light from a small source such as a built-in flash creates a harsh light with dark shadows and bright highlights, so a photographer will use tools like umbrellas and softboxes to increase the size of the light source to get a more pleasing effect.

In situations where something like a big umbrella is not practical, such as dashing around a wedding reception hall, similar effects can be achieved by bouncing light off walls and ceilings or using small on-flash modifiers like diffusers and bounce cards.

Aside from changing the size of the light source, modifiers can also be used to change the angle, shape and color of the light.

Gels are translucent sheets of colored material used to change the color of light. They can be used to balance the photographer’s light to match what’s present in the environment, or to compose creative lighting setups with more striking colors like blues, reds, greens, etc…

A flash with a green gel. Photo: Rafael Santos.

A snoot is a narrow tube which fits over the flash head. A bare flash emits a cone of light; a snoot constricts the shape of that light into a narrow beam.

A homemade cereal box snoot. Photo: Dustin Diaz.

A grid is similar to a snoot in that it also shapes the flash output into a narrower beam, but the resulting light is softer. It does this via its honeycomb-patterned construction.

A homemade grid. Photo: Thor-Erik Rødland.

A barn door is a flap or flag-looking accessory that attaches to the light source and is used to prevent light from spilling out in unintended directions.

In addition to purchasing professionally manufactured equipment, there is plenty of room for D.I.Y. light modifiers. This can be ideal for hobbyists who want to experiment without spending a lot of money. For example a grid can be made by gluing together black straws in a honeycomb pattern, and a snoot can be made from a cereal box.

The Very Basics

Understanding lighting is a challenging thing for many new photographers. Hopefully this article has helped you get down the basics needed to start thinking about using lights creatively. What it comes down to is that adding your own lights to the equation is a great way to overcome or even completely ignore poor or challenging lighting environments, and you can use all sorts of tools to diffuse, shape, color and otherwise control your light.

• Soft Diffuser
• Honeycomb/grid
• Snoot
• Barndoor
• Mini reflector
• Globe diffuser
• Flash adaptor

The kit has adaptor models for Canon, Nikon, Sony, Pentax, Vivitar and Metz flashes. For a hands-on review of this kit and some sample photos, check out “Brando Accessories Kit” by David Tejada.

Link via Mike Calanan on Twitter.

Larson’s lighting guide goes through five common shots seen in corporate portraiture, complete with diagrams of camera, strobe and subject positioning. The types of shots he covers are:

1. The Simple Studio
2. Exterior Spaces
3. People and Props
4. Confined Spaces, Multiple Faces
5. The Close-Up

Much of the technique discussed here boils down to a few simple rules — as far as lighting goes, get the flash off-camera to illuminate your subjects from the sides with nice, soft light.