III. DISCUSSION
16
Processing Parameters
The Digital Rebel XT camera has the same range of
image processing parameters as the EOS 20D:
Parameter Set 1 (contrast, sharpness and color
saturation set to +1) is optimized for vivid, sharp
images upon which no retouching will be performed
before direct printing. Parameter Set 2 (contrast,
sharpness, color saturation and color tone set to 0, i.e., mid-scale), is optimized for
images that will be retouched or adjusted. Parameter Sets 3, 4 and 5 can be
customized by the user for contrast, sharpness, color saturation and color tone. There
is also a monochrome Parameter Set that makes black and white photography easy
and great fun. This set incorporates five levels each of contrast and sharpness in
addition to filter effects (none, yellow, orange, red and green) that are just like camera
filter effects and toning effects (none, sepia, blue, purple, green) that use digital
processing to produce prints that look like vintage photochemical artifacts In the
Basic Zone modes, Parameter Set 1 is set automatically. In the Creative Zone modes,
all six Parameter Sets are available.
Custom Functions
The EOS Digital Rebel XT camera adds nine of the
EOS 20D’s eighteen custom functions to its arsenal
of controls.
C. Fn. 1 changes the functions of the SET button and the
cross keys and provides for quick and easy access to
frequently used functions. The five choices are: 0,
Normal; 1, SET button controls image recording quality;
2, SET controls processing parameters; 3, SET controls image playback; 4, cross keys
control AF point selection.
C. Fn. 2 enables the dark noise subtraction noise reduction function
for long exposures. It provides clearer images of night scenes or the night sky but
doubles image processing time between exposures.
C. Fn. 3 sets the flash sync speed in aperture priority auto mode to a fixed 1/200
second or leaves the sync speed on auto/slow sync.
C. Fn. 4 determines selectable functions for the shutter and AE lock buttons. The four
choices are: 0, AF/AE lock; 1, AE lock/AF; 2, AF/AF lock, no AE lock and 3, AE/AF,
no AE lock.
Monochrome
Monochrome (R Filter)
Sepia
