Chapter 1
for common output devices. An elegant way to enhance the dynamic range significantly. The histograms of the respective images are showing, that the whole dynamic range was never reached with one single exposure. Only in the undermost image, which is a tonemapped HDR image, the histogram is showing the full dynamic range, from the darkest to the brightest tonal values.
Fig. 1.10 The figure shows an auto exposure bracketing with five single images.
1.5 Important formats for the HDRI-Photography: JPEG and RAW-format Nowadays modern digital cameras provide the photos in jpeg- and RAW format. With special software tools, the so-called RAW converters, such as the RAW converter from Adobe Photoshop CS6, the RAW files can be edited and then converted to an 8-bit format, for example a jpeg format. Raw files contain much more information than 8-bit images and have a wider dynamic range. Although RAW formats do not have the dynamic range of an HDR-image, they provide the highest amount of data in one single image, depending on
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Wagner, Reinhard & Kindermann, Klaus, 2010: 28 ff. Bloch, Christian, 2008: 35 ff. HDR Photography - A Practical Guide
the capacity of the sensor of the digital camera18. Often the RAW formats comprise additional metadata19. There are many different RAW formats on the market such as .raw, .nef or .dng. Since there exist no standard RAW format, the saving of data in this format is problematic. Usually RAW formats have colour depths between 10 and 14 bit/channel. Due to their higher amount of data RAW images can be processed very detailled with a RAW converter before they are converted into an 8 bit format. But still several software programmes cannot display at all any RAW formats. For output devices, for example for printers, or