Here's a little something I just through together. I have two shots of my uncooked dinner last night. The left photo was shot with ambient light and the right with a Canon 580EX II and shoot through umbrella triggered by a PW. Here's the exif for the two shots. Ambient: Camera: Canon EOS 30D Exposure: 1/60 Aperture: f/2.8 Focal Length: 135mm ISO Speed: 640 Flash: Camera: Canon EOS 30D Exposure: 0.004 sec (1/250) Aperture: f/2.8 Focal Length: 145 mm ISO Speed: 100 As you can see, the ambient is still vastly underexposed with just the kitchen lights. I even had the ISO speed up to 640. I could have went higher, but then you're looking a a photo with less quality at larger resolutions because of noise. The shot was also taken at 135mm at 1/60. If I would have not been shooting with the 70-200 f/2.8 IS and had the image stabilization to compensate, the photo would have been out of focus. The photo with the flash provided enough light to use an ISO of 100 and the max sync speed of 1/250. And you can see with the proper modifiers and techniques, like the shoot through umbrella, that you don't have hard light, harsh shadows, or an over all non-desirable effect on the picture. If you look you can even see that the shadows in the photo with the flash are even softer than with ambient light.