Re: Of black point compensation
Re: Of black point compensation
- Subject: Re: Of black point compensation
- From: Joel <email@hidden>
- Date: Wed, 27 Jun 2001 10:42:58 -0500
From: Henrik Holmegaard <email@hidden>
There is a lot of confusion over black point compensation, so here's
the logic of how it works:
(clip)
Or to put it briefly, because
a. Perceptual is white point and black point relative,
b. Relative Colorimetric is white point relative and black point absolute, and
c. Absolute Colorimetric is white point and black point absolute.
Then to separate with Relative Colorimetric, the black point should
be relative and not absolute, which is what Black Point Compensation
does.
And to soft proof and proof print with Relative Colorimetric, the
black point should be absolute as otherwise the lighter offset black
gets mapped to the deepest black of the monitor and proofer, which is
what Ink Black does. The implementation for Adobe tools until PS6 was
to soft proof with relative white and relative black, dressing up the
grayish black of the printed page in more eye-catching designer black
-:).
Simply saying to separate with Perceptual and proof with the standard
implementation of Relative Colorimetric with absolute black (: no
BPC) works every time. And is also easy to understand, no?
Excellent post! Makes perfect sense. Thank you!
And, no, it's not easy to understand till one reads to the very end.