Wednesday 30 January 2013

Project Working Space


Project Working Space
The proper choice of a working space is the one that
typically matches the “output intent,” the color space

corresponding to the target device. The Working Space
menu containing all possible choices is located in File >
Project Settings (Ctrl+Alt+K/Cmd+Opt+K, or just click
where you see the “bpc” setting along the bottom of the
Project panel).
Profi les above the line are considered by Adobe to be the
most likely candidates. Those below might include profi les
used by such unlikely output devices as a color printer.

By default, Working Space is set to None (and thus Color
Management is off). Choose a Working Space from the
menu and Color Management is enabled, triggering the
following:
. Assigned profi les in imported fi les are activated and
displayed atop the Project panel when it’s selected.
. Imported fi les with no assigned profi le are assumed to
have a profi le of sRGB IEC61966-2.1, hereafter referred
to as simply sRGB.
. Actual RGB values can and will change to maintain consistent
color values.
Choose wisely; it’s a bad idea to change working space
mid-project once you’ve begun adjusting color, because
it will change the fundamental look of source footage
and comps.
Okay, so it’s a cop-out to say “choose wisely” and not give
actual advice. There’s a rather large document, included
on the disc and also available at www.adobe.com/devnet/
aftereffects/articles/color_management_workfl ow.html,
that includes a table itemizing each and every profi le
included in After Effects.

We can just forego that for the moment in favor of a concise
summary:
. For HD display, HDTV (Rec. 709) is Adobe-sanctioned,
but sRGB is similar and more of a reliable standard.
. For monitor playback, sRGB is generally most suitable.
. SDTV NTSC or SDTV PAL theoretically let you forego a
preview broadcast monitor, although it’s also possible to
simulate these formats without working in them (“Display
Management and Output Simulation,” below).
. Film output is an exception and is discussed later in
this chapter.
To say that a profi le is “reliable” is like saying that a particular
brand of car is reliable: It has been taken through
a series of situations and has caused the least problems
under various types of duress. I realize that with color management
allegedly being so scientifi c and all, this sounds
squirrelly, but it’s just the reality of an infi nite variety of
images heading for an infi nite variety of viewing environments.
There’s the scientifi cally tested reliability of the car
and then there are real-world driving conditions.
Gamut describes the range of possible saturation, keeping
in mind that any pixel can be described by its hue,
saturation, and brightness as accurately as its red, green,
and blue. The range of hues accessible to human vision is
rather fi xed, but the amount of brightness and saturation
possible is not—32 bpc HDR addresses both. The idea is to
match, not outdo (and defi nitely not to undershoot) the
gamut of the target.
Working spaces change RGB values. Open sanityCheck.tif
in a viewer and move your cursor over the little bright red
square; its values are 255, 0, 0. Now change the working
space to ProPhoto RGB. Nothing looks different, but the
values are now 179, 20, 26, meaning that with this wider
gamut, color values do not need to be nearly as large in
order to appear just as saturated, and there is headroom
for far more saturation. You just need a medium capable of
displaying the more saturated red in order to see it properly
with this gamut. Many fi lm stocks can do it, and your
monitor cannot.



No comments:

Post a Comment