More real than real.

After reading an article in the German news magazine "Der Spiegel", which described in detail the new HDR (High Dynamic Range) photography a few days ago, I decided to take a look at it myself. Should there finally be an alternative to graduated neutral density filters?

The problem that often plagues photographers is as follows: Cameras have a very limited capability of recording contrast, so images of motives very rich in contrast will invariably have to exhibit some trade-offs, some corner-cutting.

Let's take a run-of-the-mill sunset image for example: A darkening mountainous landscape with exciting textures and shades of rock and snow; above the mountains a bright fabulously lit sky filled with pink and red clouds.

When taking a picture without the help of any tools, it usually comes down to two options - either adjust the settings to optimize for the bright sections of the image, and thus losing all other areas to the shadows (in our example a fabulously lit sky, but the foreground is dark as night and will lose all it's features and texture), or optimize for the darker parts of the image, and thus "burning" out the bright areas (the sky will turn completely white or pink and the individual clouds would be lost).

Traditionally this problem has been solved with so-called "neutral density" filters - essentially slabs of glass that are mounted in front of the camera and which have the upper half darkened, and the other one as clear glass. This allows to artificially darken one half of the image, and allows the photographer to expose the image longer without burning out the bright areas. It works great for images where there is a clear, straight line separating the bright from the dark sections of the image (like a horizon). It's not that great when patches of bright and dark are all over the image.

Instead of trying to get all the information into a single image, for the new HDR technology three (or more) images are taken, and only later combined into a single new image. One of them is deliberately underexposed to record all features of the bright sections, one of them is normally exposed to capture the mid-range, and the third is overexposed to gather all information about the dark parts of the image. I was curious about this, so I downloaded the sample software and took a series of high-contrast shots in Dublin yesterday.

First the three shots taken, the center one being the "normal" exposure. You can see the problems of the foreground being too dark (on the leftmost) or the sky being burned out (rightmost) quite well:



Then the combination with the Photomatix HDR tool:


The results are staggering: Every cloud of the sky is still visible, and so are the green color and the features of every plant in the foreground.

And this was just a few handheld shots in the afternoon. Using a tripod will produce much crisper results and much less ghosting. Some amazing examples can be found at the Photomatix website

The original Spiegel article which prompted me to try this myself can be found here