If the Autoexposure check mark is not present, as seen in Figure 13.4, this indi-
cates that the plug-in does not have autoexposure information on the film presently in
the scanner. If the check mark is not present and the Autoexposure check box is
checked, an autoexposure operation will occur the before the next scan.
Figure 13.4
A
UTO
check box with no Autoexposure check mark indicates an autoex-
posure will occur before the next scan – Macintosh and Windows.
Brightness
The plug-in’s Brightness controls allow you to adjust the overall brightness of
the scan.
The correct brightness setting is critical to attaining high-quality scans. This is
because the dynamic range of the film is greater than the dynamic range of the imaging
system, requiring tonal compression in the software.
It should be noted that the brightness control also has a global effect across the
entire scan. As with contrast, accurate local control can be attained by modifying the
gamma curves, which will be discussed in the following chapters.
For example, increasing brightness is a good way of increasing the overall readabil-
ity of an underexposed image. Essentially, it allows more light through the film.
However, care must be exercised when increasing the brightness, especially if there are
large bright areas (highlights) in the film. If strong highlights are present and the bright-
ness control is boosted, these areas might saturate (overexpose, or 'wash out') reducing
or eliminating detail in these areas.
Similarly, problems can occur if the brightness is reduced to provide increased
definition in the highlights. This can cause information in the shadows to be further
underexposed, causing a loss of detail in these regions.
The approximate results of changing the brightness can be seen while the preview
image is on the screen. However, as you have learned here, care should be taken when
performing these adjustments.
Adjusting Brightness
Macintosh: The Brightness button in the Scan dialog, the white circle with the
small lines radiating from it, enables you to set the brightness value either through the
associated Brightness value edit box or Brightness slider. The Brightness value edit box
can be changed by clicking in the box and entering the new value. The Brightness value
can range from 25 to 100 for Coolscan, and 0 to 255 for LS-3510AF. Clicking on the
Software Reference for Scanners
Page 121
Chapter 13
Contrast, Brightness and Color Balance
Summary of Contents for Scanners
Page 1: ...Software Reference for Scanners ...
Page 14: ...Page XIV Software Reference for Scanners Table of Contents ...
Page 36: ...Page 22 Software Reference for Scanners Software Installation IBM PC or Compatible Chapter 3 ...
Page 126: ...Page 112 Software Reference for Scanners Cropping and Sizing Images Chapter 11 ...
Page 132: ...Page 118 Software Reference for Scanners Film Type and Orientation Chapter 12 ...
Page 146: ...Page 132 Software Reference for Scanners Focusing with Coolscan Chapter 14 ...
Page 170: ...Page 156 Software Reference for Scanners The Gamma Curve Editor Dialog Chapter 16 ...
Page 194: ...Page 180 Software Reference for Scanners Troubleshooting Windows ...