This was a quick portrait from the top of a building in NYC the other morning. It was an impromptu session, so there were no lights, umbrellas, or softboxes. I just had to work with the available light of late morning. So what does a photographer do in a situation like this? First, shoot RAW. This will allow you some more control in the digital darkroom. Next, bracket your exposure, and use your histogram to keep the highlights under control. I pushed my exposure as far as I could and stopped just before blowing out the whites. Then, in the digital darkroom I rescued the detail in the shadow areas. In Photoshop CS4 I used a layer mask to desaturate the background, while leaving my subject the same. Next, I used a second mask to add a bit of sharpening, and a third mask to apply a slight vignette.
If I had the option of bringing lights, I would have underexposed the ambient and used a few off camera flash units to illuminate my subject. This would have eliminated the need for most of the post production work mentioned above. I believe it is always best to get it right in the camera when at all possible. However, for a mid morning shoot in direct sun, learning how to maximize your cameras RAW files can save the day.