Your portrait is sharp, the exposure is right, the model looks good. And the image still looks flat. Nothing is technically wrong, which makes it hard to fix.
What is usually missing is a decision about the light. Where does it come from, how big is it, and what should the shadows do? This post walks through those decisions in the order they matter, starting with a single flash.
What is the best way to start with off-camera flash?
Start with one light, on a stand, off the camera. Put it about 45 degrees to one side of your subject and slightly above eye level, aimed at the face. Take a frame. Then move the light in a slow circle around the subject and take a frame every few steps.
Look at what happens under the nose, along the cheekbone and on the far side of the face. You are learning where shadows land for each position. Most portrait setups you have admired are variations on this one light.
Do this with a real person, not a chair. Skin, hair and eyes react to light in ways a stand-in cannot show you.
How do size and distance change the look of the light?
Softness comes from how large the light source appears from where your subject sits. A 90 cm softbox two metres away looks small to the face, so the shadows are crisp. The same softbox 60 cm from the face looks large, so the shadows blend gently into the highlights.
Moving the light closer has a second effect. Light drops off fast with distance: double the distance and the light reaching the subject falls to a quarter. With the flash close to the face and the background further behind, the background gets very little of it and goes dark. This is the simplest way to separate a subject from a busy wall.
So you have two dials. Closer means softer and a darker background. Further away means harder light and more even coverage of the scene.
Where should the shadows go?
Pick the mood first, then place the light.
Light near the camera axis, from the front, gives an even, open look with few shadows. It is safe and often flat. Light at about 45 degrees gives shape to the face and works for most portraits. Light from 90 degrees to the side splits the face into a lit half and a shadow half, which reads as serious or dramatic. Light from behind the subject, aimed back toward the camera, traces the edge of hair and shoulders.
If a portrait feels dull, move the light further around the subject before you change anything else.
How do you balance flash with the light already in the room?
Shutter speed controls the ambient light. It has almost no effect on the flash, as long as you stay at or below your camera's flash sync speed. Aperture affects both. Flash power controls the flash only.
That gives you a workable routine:
First, set your exposure for the background without flash. Choose the shutter speed and ISO that give you the sky or room brightness you want. Then add the flash and adjust its power until the face looks right. If the background is too bright, raise the shutter speed until you reach sync speed. If you need to go past it, use high speed sync, which lets you shoot at faster shutter speeds at the cost of flash power.
If your flash is too powerful for a wide aperture in daylight, lower its power, move it further back, or add a neutral density filter to the lens.
What does a second light add?
A second light should have a job you can name in one word: fill, rim or background.
Fill lifts the shadows. Try a reflector first. It costs almost nothing and gives you a soft fill that follows the main light. Use a second flash for fill only when the reflector cannot do the job.
A rim light sits behind and to the side of the subject, aimed at the edge of hair and shoulders. It separates the subject from a dark background and adds a bright outline.
A background light shapes the wall or backdrop behind the subject. Put a flash on the floor aimed at the backdrop and you get a gradient of light that adds depth.
Add lights one at a time. Take a frame after each. If you cannot see what a light contributes, switch it off.
Which light modifier should you use?
A softbox gives soft, controlled light and suits most portraits. A beauty dish is a little crisper and gives more contrast on skin and eyes. An umbrella is quick to set up and throws light wide, which is handy on location. A grid on any of these narrows the spread and keeps light off the background.
If you own one modifier, make it a mid-size softbox with a grid. That combination covers a lot of ground.
Three habits that improve your lighting fast
Check your catchlights. The reflections in the eyes show you the shape and position of your main light, and they show up in the final image. Make sure they look intentional.
Test with the model in position. A stand-in can save time, but the final adjustment always happens on the person you are shooting.
Change one thing at a time. If you move the light, change the power and swap the modifier in one go, you will not know what improved the image.
Learn faster by watching someone light it, then doing it yourself
Reading gets you the vocabulary. Seeing an experienced maker place a light, take a test frame and adjust it in real time teaches you the sequence of decisions. Doing it yourself on the same setup, with a professional model, makes it stick.
That is the format of our events. You watch an international maker work, from concept to shoot, and then you step onto the set yourself, with professional models, light and the latest gear. Most of our events and roadshows sold out within days, so follow us to hear first about new dates.