Digital Image Formats - A Practical Guide to Video and Audio Compression - page 126

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Figure 6-6 Safe areas.

Only a small amount of restorative work was done, but the vast improvement in quality
came by working from a previous-generation master rather than simply digitizing a print
that had been optically combined. With the advent of DVDs there has been a surge in
demand for old movies to be restored and compressed using good-quality encoders in
order to make them available to a new generation of consumers.

6.9.1 Dynamic Range

The imaging quality of the D-cinema format is improving all the time. When shooting this
material with a completely digital video camera, the dynamic range of the content at the
dark end of the intensity scale is still not as good as analog film. The detail is simply not
there although it is improving year by year. Some compensation for this takes place in a
film-to-D-cinema transfer. Where there is detail to be extracted, changing the gamma
curve and adjusting the input-to-output intensity mapping will reveal subtle shading in
dark-shadowed parts of the picture. Shooting must take place with strong lighting being
carefully bounced into all the shaded areas of the scene.
Shortly, we will examine some of the work on high dynamic range imagery (HDRI).
This technique will lead to some significant improvements in the quality of digital pho-
tography, especially where it pertains to low light conditions.

6.9.2 Film Grain

Cinematographers have fallen on either side of the fence regarding whether they like the
quality of output produced with this technology. George Lucas clearly favors shooting