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| Pertama Complex |
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| CIMB Building |
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| Green Flat Putrajaya |
From a practical standpoint, a modern digital sensor has about 7–9 stop tonal range. This doesn't allow us to capture wide tonal range images accurately. What we end up with in this case is an image that must favor either the shadows, or the highlights.
By using multiple exposures and merging them, HDR allows us to extend that tonal range and capture detail all the way from the brightest highlights to the darkest shadows.
I refer to figure 1 again. In this image, we are able to see detail on the sunlit water, as well as in the shadows of the tree. If this had been shot with one capture, either the highlights would have been blown out, or the shadows would have blocked. This was shot as a 9 stop bracket, allowing good detail throughout.
There are two types of contrast ranges: Global and Localized.
The image above is an example of controlling Global contrast to achieve continuous detail throughout the image. In this case, we want to make the entire contrast range fit our output. Without this treatment, either end of the tonal range might be compromised.
But there are times when we come upon a scene that seems to have a normal tonal range, yet when we look at the file, we find that shadows have no "meat" to them or highlights are hot and lifeless.
Figure 2 is one such image. Seemingly, it has a soft tonal range, but in fact is a very complex image, encompassing at least two separate tonal ranges. This is an example of localized contrast. In it, we have the bright highlights on the steam pipes of the train. We also have micro contrast areas deep down in the shadows, which need to have detail. Global contrast is represented in the entire overall tonal range of the bright highlights down to the deep shadows. However, without attention to the localized contrast in the shadows, they would have died,
Even though this image was captured on a cloudy day, it still benefits from an HDR treatment. It is monochromatic. Yet because of all of the minute highlights and dark areas, it has more contrast that one might think.
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