When lighting a portrait remember to keep it simple. Consider the use of one light and modifier at first. This is considered your main light and set the power according to your preference and vision. Take a few test shots to determine if the light matches your vision and adjust accordingly. The use of the histogram on camera may be of use to determine proper exposure. Since this image was shot outdoors, Instead of adjusting the power of the flash I simply moved it away from the subject. A second light can then be added to “fill” the shadows. This light is usually set to lower power than your main light. More lights can be added but I rarely find it necessary to use more than two or three lights and a reflector at most for portraits.
In the example below the image was shot outdoors with camera and flash’s in manual mode for total control over the lighting.The main light set to 100% power. The second light used as a fill only set to 20% and distance of flash to subject both adjusted. Both lights were used with white umbrella modifiers for a softer light. Although umbrellas tend to “spill” light and not my first choice for indoor or studio lighting they tend to work fine for outdoor use since “spilling” of light isn’t as much of a concern outdoors. For indoor use I do prefer using light boxes with grids for more control of the direction of the lights and therefor less spilling.
In Post production the image was converted to black and white to place more emphasis on the subject and avoid distraction of the background.
One of the most important aspects of photography is learning how to control light.I chose the two images to the left for examples.
The first image was shot outdoors at sunset. To capture this image without turning it into a silhouette two key techniques were used:
1.The background was metered with the camera in aperture priority. (auto can be used too)The point is you want to get a meter reading. The camera may have said f11 at 1/250 sec. Knowing what the camera needs to accurately expose the background at this setting now we can “manipulate” the light.
I switched the camera into manual mode and changed the settings to f12,f14,f22 etc. and took a test shot till I was happy with the amount of light I was letting into the camera for the background. Basically I was darkening the background so not to drown out the main subject.If I cared about the depth of field I could have changed the shutter speed for the same effect.
2.The next step is to add fill light of the subject or he would appear too dark to be seen in the image. To accomplish this I added flash. I used 2 strobes. The key strobe was positioned camera left and slightly above the subject. I played with the intensity of the light till I was happy with the results. The second strobe was placed camera right and low to add a minimal amount of fill light to his left side as to bring out some detail. The power intensity is set very low on this strobe as to not compete with the key light.
I didn’t use any light modifiers of diffusers on the flashes with this image because I wanted it to be a little “hard” so the main subject in the foreground would stand out from the sunset background.
The second image was shot without any flash. The camera was set to aperture priority at f3.5. The natural light from this window was soft and diffuse from an overcast sky.Also there was a window camera right that added some soft fill light to the shadows to bring out some detail in her dress. This soft light works well with this image and use of flash is not only unnecessary but could degrade the image.
When used correctly, both artificial and natural light play a key role in the overall feeling the photographer is trying to convey to the viewer. With patience and practice use of correct lighting can produce a successful image.