Taking great portraits outdoors is possible with a little planning.
Since the sun is the ultimate source of natural light, it seems almost intuitive that taking pictures outside would be easier than using studio lighting. However, the truth is that the sun is a difficult lighting source to properly master, resulting in many under- or overexposed, overly shadowed photographs from outdoor sessions. Even if you are using an amateur point-and-shoot camera, a few simple tips will help you work outside to keep your photos evenly lit and well-exposed in any situation.
Find the Shade
One of the mistakes commonly made by outdoor photographers is assuming that more light is better, so their subjects stand in direct sunlight. This produces harsh shadows and overexposed highlights, not an evenly lit portrait, and leads to a lot of squinting for your subjects. A simple solution to this problem is to pose your subjects in the shade. Objects such as awnings, shadows, trees or even some convenient cloud cover diffuse the light, making it fall more evenly on the subject and eliminating high contrast shadows. Just be aware that your camera's automatic white balance feature should be activated for this, since whatever is causing the shade can also add a color cast to your final image.
Use Fill Flash
Another common mistake in outside photography is assuming that the sun is your only light source and since it's bright out, you won't need your flash. This is a mistake -- fill flash is a great way to fill in high contrast shadows and separate subjects from their background for a more dynamic image. Set your camera's settings to fill flash before taking your pictures. If possible, aim the flash indirectly at your subjects or use a diffuser for an even more subtle fill-flash effect.
Timing Matters
If you have the luxury of scheduling the timing of your outdoor shoot, there are good times and bad times to take outdoor pictures. High noon is a bad time, since the light is at its harshest and shadows are at their most contrasting. Morning or afternoon shoots are better, with morning shoots in natural sunlight providing a ruddier light, and afternoon shoots having a more violet hue. The quality of the light matters when shooting outdoors!
Reflective Thoughts
Don't be afraid to use reflective surfaces to bounce natural light into the shadows. These don't have to be studio reflectors, any reflective surface will do. Try posing your subject next to a brightly colored wall or object to bring more light to the image. A 3-by-3-foot piece of white foam board is an excellent reflector. Even standing someone in a reflective colored shirt nearby will change the photograph and lift the shadows. Experiment with moving the light around, and your outdoor pictures will be more even and well lit.