Here is a quick example on the advantages of using a flash off the camera for filling in the shadows. These two shots are straight from camera and were taken with in seconds of each other. The shot on the left was taken using only available light and the one on the right was shot using a Nikon SB600 speedlight off to the right for fill.
1/800 ( Nikon D40 has a high flash sync speed)
Nikon 35mm 1.8 AF-s Lense
Nikon D40 body
And if you are wondering how could I be shooting an 1/800 and still sync with a flash, well that is the beauty of the Nikon D40 and its digital shutter 🙂
The natural shot has only the sun as the only source of light. It was a late evening sun, which is fairly low in the sky. Direct sunlight also casts some hard shadows that you can see on Hannah’s right hand. Due to the nature of digital camera, their dynamic range is about 2-3 stops max , after this you will start to get burnt out highlights or black shadows with no details. I don’t own a light meter so I can’t tell you what the light ratios were in this set up. I would hazard a guess at it being near the 2 stop mark as the skin in light is properly exposed while the dark part of the leg, although darker could still be brightened in photoshop and detail recovered.
Fill light is the term used to fill in shadows i.e. to brighten up dark areas in a scene / photo. The amount of fill light depends on taste and the look needed. Too much fill light and the image could look flat or worse cause some extra confusing shadows i.e. check out the back of the surf board in this example. Not enough fill and there still may not be any detail in the shadows.
There are a few ways to introduce fill light. You can use other lights at lower power settings or you can use reflectors to reflect back some of the main light onto the subject. A reflector can be anything really, but the best reflectors are usually silver, white or shiny gold materials.
Lately I have being using flash to fill in the shadows. I typically set up my flash off-camera and I trigger it using radio transmitters. They have a range of about 20feet so it means that the flash can be place all around a model. The advantage of taking the flash off the camera is that on-axis fill, i.e. fill light from the camera can look boring and flat. This is the kind of light that you get from your compact camera where the flash is built into the body. Taking the flash off the camera axis changes the direction of the shadows and add’s some interest to a subject….. well thats the plan anyway 🙂
So the set up for this is simple. The sun is the main light on the left and is causing shadows on the right. I set up a flash on the right, pointed back at the model to fill in these shadows. I used a 1/2 CTO gel to balance the light from the flash to match the sunlight. The zoom on the flash was set to its widest to spread out the light and the power settings was adjusted manually. I can’t remember the exact power setting, but it would have been around 1/2 to 1/4 power.
Below is a quick diagram of the light set up