of the most user-
friendly and intuitive
of the many RAW
data-processing
software packages
on the market, so
even if you're a
beginner, you'll find
it simple to turn
your images into
finished photos. The
Adjustment Controls
Palette contains
exposure, contrast,
shadows, highlights,
color saturation,
sharpness, and
the X3 Fill Light
feature. A new noise
reduction control
area allows for reduction of both
color noise and luminance noise.
The Color Wheel allows for easy
adjustment of photograph colors.
Simply adjust these parameters and
watch the image change in real time.
That's all it takes to recreate the ideal
photo you had in your mind's eye as
you pressed the shutter.
X3F: A Proprietary file format for
outstanding texture and color
In fact, shooting in X3F format has
other advantages too. In a digital
camera, the image signal captured in
RGB is recorded by being converted
into what is
known as YCbCr
color space.
The Y stands
for brightness,
and the CbCr
stands for color
difference.
In an ordinary
digital camera, a
file format known
as YCbCr 4:2:2
is used, where
the color signal
is set to half the
brightness signal.
This format was
developed in
order to send
color information
efficiently on the limited bandwidth
available back when color television
was first developed. Designed on
the principle that the human eye is
less sensitive to color data than to
brightness data, this historical format
has survived intact to this day, and is
still used as the mainstream format in
digital cameras.
However, now that digital camera
performance has improved so
dramatically, people are using their
photos in different ways, displaying
enlargements on their computer
screens, and large photo prints
are mainstream. Today's output
conditions are getting better
and better. The old YCbCr 4:2:2
format was designed for efficient
signal transmission, and not for
high-quality output. To our way
of thinking, this format no longer
adequate to meet the needs of
all photographers.
X3F images preserving
the balance of the natural data
The JPEG files from the DP series
are output in YCbCr 4:2:2 in
compliance with the Exchangeable
image file format (Exif)
pecification, which is the standard
specification for file formats. But
in the direct image sensor, each
pixel location captures the full
complement of RGB color data, so
in X3F files, which is the RAW data
format, brightness data and color
data can be kept in a 1 : 1 ratio
without relying on interpolation.
When this image is processed in
Sigma Photo Pro, even if it is saved
as a JPEG, if the JPEG quality-
setting selected is 7 to 12, it will be
saved as YCbCr 4:4:4. The DP's
image quality, with its amazing
vividness and texture, is really
due to the X3F image data, which
preserves the balance of the natural
data. For the best photos with the
best image quality, we definitely
recommend shooting in X3F mode.
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