Modern digital cameras have revolutionized photography. In the past, when a camera film contained only 36 frames, the wise amateur photographer didn't take risks and stuck with things she knew about. The unlimited number of shots you can take on a modern digital memory card opens up new opportunities, and if it goes wrong you just wipe the shot and try again. Good photography in dark buildings, such as churches and cathedrals, is still a challenge for the amateur, but professionals have a secret weapon. They use a technique borrowed from forensic science and astronomy; High Dynamic Range photography, or HDR imaging.

Things You Will Need

Digital camera

Step 1

Mount your camera on a sturdy tripod. Compose your shot and examine it carefully. Note the areas of bright light and the areas of deep shadow. Traditionally you would need to expose for one extreme or the other. If you expose for the bright light, you will lose the shadow areas into deep black. If you use a long exposure to bring out the shadow areas, the well lit areas will be over exposed and rendered as pure white with no details.

Step 2

Set the camera to the aperture priority setting and, if available, set the ISO to 100. Look through the view finder and note the exposure recommended by the camera. Your camera will have calculated the exposure it thinks will best cope with the overall lighting in the shot. This is the exposure to use as a base line for a series of shots.

Step 3

Set the exposure 2 EV stops (-2) below the average setting and take a shot. Change the setting to -1, 0 +1 and +2 EV and take another shot at each exposure. If the range between the light and dark extremes isn't vast, take only sufficient images to cover the exposure range.

Step 4

At home, combine your images using any of a variety of free software packages. Popular free software includes FDRTools Basic, Picturenaut and Photomatix Basic. Commercial packages such as Photoshop also have HDR functions built in to them.

Using the software is straight forward. Load up the images, select from the options offered and view the results.

HDR images can occasionally have a slightly surreal look about them, but this can be corrected during the blending process. The surreal look is partly because we are used to photographs NOT representing images as we see them with our eyes. When we see an image taken inside a cathedral, yet correctly exposed across the entire range of lighting, our brains notice that is is not what we usually expect.

Tips & Warnings

No more than 5 or 6 exposures are needed for an HDR shot. Anymore than 6 adds very little additional detail and takes a lot longer to process at the software stage.