[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

re: Legal RGB

Steven Flippin wrote,

>My question is more concerned with RGB -
>YUV color space conversions.
>With all of the RGB devices in our
>environment today, how are post facilities dealing with this issue, or
>are they dealing with it at all. If a spot is leaving Xfer and moving on
>to say Flame, is the colorist trying to conform to RGB legal limits.

Going that way, RGB to YUV,  isn't normally a problem.  While RGB fits and
displays nicely in YUV space, the reverse parallells the analogy of forcing
a square peg into a round hole.  

Dealing with it practically in telecine, there are several tools.  One is
the eyeball.  Another is (in daVimci 8:8:8, et al) RGB limiting which
conforms the signal out of the daVinci into legal RGB space.  It has it's
limitations, creatively, but otherwise is fairly accurate, though not always
approriate.  The third tool is a Tek 601 (or WFM 300) component scope with a
provision to light a "GO-NO GO"  tally when RGB limits are being exceeded.
It does not tell you what particular component is out of limits though.  The
last is a device made by HP, (the name escapes me.  "Color Crusher" or
something) that sits in the monitor path for instance and annoyingly
highlights the illegal pixals in the dispaly.  It also conforms the signal
if chosen by the user.

We use the daVinci RGB limit, scopes, and eyeballs to help us keep it legal.
I've yet to be arrested.....correction.....convicted.