Many of you might be familiar with the term HDR Photography, or more specifically, High Dynamic Range Photography. So just what is it?
Most digital cameras can capture a range of light and dark “areas” of a scene of approximately 5 F-stops. Meaning, if the darkest area of a scene’s reflected measurement is F4, and the brightest area measures at F 22, that’s five F-stops (F 4, F 5.6, F8, F11, F16, F22).
What if the difference between the darkest and brightest area of a photograph is more than a 5 F-stop range, such as this photograph?
Well, typically, you’d have to decide what’s more important; the detail in the brightest areas, or the detail in the darkest areas? In the photo below, if we exposed the dark wall base that meets the floor properly, then the windows and walls all get blown out.
In the below image, if we expose for the window light properly, then everything else is pretty much too dark.
If we don’t expose for the floor (darkest) or the windows (brightest), but instead expose for something in between the bright area and the dark areas, say, like the columns, we get the image below, where the darks are too dark and the brights are too bright:
Neither of the three images is a good image by itself, but the lighting range of the scene is so much more than 5 F-stops, that we cannot accomplish a great image with just one exposure, because the Dynamic Range is so great.
So here’s what I do. First, I make an exposure based on an exposure reading of the brightest part of the scene, using a hand-help spot meter to get my reading, with my camera snugly secured to a tripod so there is no movement during the three images I am about to take. Secondly, I take an exposure reading and snap an image based on a medium tone of the scene, in this case, the columns. Lastly, I take a third exposure reading and snap an image based on the darkest part of the scene, such as the dark wall near the floor, or a dark area in one of the distant archways.
Now, you can also use your camera’s built in spot meter to take the measurements as well if you can zoom in on an area, which is tough with a wide angle lens. You would take all three measurements before securing your camera to the tripod.
Then, using one of the many HDR processing software programs available, I merge all three images together to accomplish the finished image below:
Keep checking my workshop offerings to catch a more intensive HDR workshop or training.