Using Flash and Reflectors in Your Portrait Photography
Thursday, April 22nd, 2010©2010 Natalie Fobes
Flash vs. Reflectors
Advantages of using a reflector to fill vs flash fill
1. Don’t always have a lot of light to reflect or the angle isn’t right to reflect the light
2. Can create pools of light instead of filling the whole scene: handy when subject is framed by something like vegetation or a door
3. Often more natural with catchlights that are more subtle
Advantages of flash fill over reflector
1. Flash is on-camera (most of the time) where you need an assistant or special gear to hold a reflector
2. Not affected by the breeze
3. Can fill a subject that is further from the camera
4. Can automate with ttl flash units for fast changing situations
5. Can clean up the color of the light
Flash on camera
Flash on camera is a versatile tool. We often think of the bad examples of it…the deer in the headlights look. We all have some of those in our files.
But with a little thought and understanding you can:
1. enhance the light
2. clean up the color of the light
3. raise the value of your subject for emphasis or to balance with the background
4. erase wrinkles and dark circles
5. create depth
6. preserve detail
7. create nice light
I routinely use flash on camera in ttl mode when photographing people. I adjust the flash output depending on whether I’m using it as fill or as a main light. Adjusting the flash output does not affect the camera’s auto exposure setting. That is controlled by the AV button on the camera.
Getting consistent results with TTL is dependent on whether you are in an auto exposure mode or manual and accurate focus. Will Crocket, www.shootsmarter.com, suggests that you use manual exposure and the single frame focus setting for maximum consistency.
In fast changing situations, like weddings and photojournalism, I routinely use ttl settings with my shutter and aperture priority auto exposure modes. I don’t use Program mode as a general rule.
I choose my focus setting depending on the conditions. In controlled situations I work in single frame focus.
But, when you are following the action you need to use AI Servo.
A couple years ago I was one of the personal photographers for the Dalai Lama when he was here for a week. I photographed him walking onto the stage at Key Arena. It was very dark backstage. I saw a white wall that I used to bounce my strobe off to diffuse the light and so as not to blind His Holiness. My settings were AI Servo focus, low motor drive and shutter-priority auto exposure. The majority of the photographs were sharp and well lit.
Bouncing off the wall made all the difference between a pleasantly lit photo and a deer in the headlights photos.
So if you are in a controlled situation, for example group shots at a wedding, I suggest you set the camera to manual exposure and then use the ttl. It will make processing the images easier and faster.
Settings for on-camera TTL flash
For fill light I set the flash output for –2/3rd of a stop to –1 2/3rd of a stop. Most of the time my flash is set for –1 or –1 1/3. I don’t want people to look at the print and say “Hey, she used flash fill.” Subtle enhancement and improvement of the light is my goal with fill.
If I’m shooting group shots and I want to fill in wrinkles and minimize dark circles, I’ll set the flash to +2/3. This gives the ambient light just a little boost. It also cleans up the light.
For a main light I set the flash for +1 to +2 depending on how dramatic I want the light to be. I then use the ambient light as the fill by slowing the shutter to either allow more light to fill in or less light to fill in. If you go any more than that you should be on manual exposure.
As you’ve learned the bigger the light source the softer the light tends to be. So, I bounce my on-camera flash off walls, celings, doors, reflectors, anything that will make the light source bigger. The light appears much more natural than direct flash.
When I don’t have something to bounce off I use the Omnidome to soften and spread the light. This is a plastic piece that fits over your flash. The trick to using it is to not point it directly toward the subject or toward the ceiling but to have the flash angled up. This maximizes the area of light from the flash.
When combining flash with ambient light the determining factor is the ambient light. Whether you create a flash dominant image where the flash is the main light source or a fill flash image using the natural light as the main light source, all of your camera and TTL flash settings are adjusted for the ambient light.
So let’s say your available or ambient light at ISO 200 is f60 at f4. You manually set your camera for that exposure. You want to fill. Set your TTL to –1 to create a one stop difference between the value of the ambient light that is the main light and the fill from your flash.
Let’s say you want to make the flash the dominant light and a little brighter than the fill. You would set your flash for +2/3rds and bounce it off the wall or ceiling.
OR if you know your ambient/available light is f4 and you want your main light to be one stop brighter then you would set your exposure to 60th at f5.6 and your flash to even. Set your TTL to +1 while keeping your exposure the same and your highlight would be two stops brighter than the ambient light.
The best way to grasp this is to create a series of photographs where you make the changes in a logical progression and then look at the differences. Be sure to take notes on what you are doing and why before you start.
The steps to using flash are as follows:
1. Is the light okay as is? Is it pleasing on people’s faces? Is the room lit well enough to photograph? Is there depth or is it too flat? What is the color of the light? Are the shadows too harsh?
2. If you want to use flash then decide if you should bounce your light or use it direct.
3. Are you using your light as fill or main?
4. How are you going to balance your light with the ambient? Is your goal to create dramatic light, soft light or just light you can work in?
5. What shutter and aperture do you need to use? (dictacted by the ambient or available light.)
6. Do you want to set your ettl at plus, even or minus?
7. Shoot
The affect of light on mood: In general the greater the ratio between highlight and shadow the more dramatic and serious the photo is.

