Re: Optical brightener
Re: Optical brightener
- Subject: Re: Optical brightener
- From: Henrik Holmegaard <email@hidden>
- Date: Mon, 3 Sep 2001 21:56:02 +0200
David Remington <email@hidden> wrote:
Glossy paper for the Fuji Pictrography measures -5 in the b channel
and there is no optional paper for that printer. With certain subject
matter this can have quite an impact. "proofing on a 9300k monitor"
is a good analogy. I'm naturally curious what white point adjustment
to the profile could overcome this. As for using a UV filter over
your measuring device, I'm split on the logic.
No, the equivalent would be - 10 (and beyond) which is what you get
in color copier papers and some inkjet papers.
If you wish to talk proofing at all, then make sure to
a. have a white point on the proofing device which is higher than on
the device being proofed (this is probably not the case with the Fuji
media as offset papers range up to L 96),
b. edit the white point to remove optical brightener (PMPro 3 and up,
for instance),
c. have a black point on the proofing device which is lower than on
the device being proofed (this is probably the case with the Fuji
media)
d. convert from RGB to the CMYK space you wish to proof with
Perceptual without black point compensation or Relative Colorimetric
with black point compensation
e. make very sure to revisit the black point compensation checkbox,
uncheck it, and then convert into your proofer space using relative
colorimetric or absolute colorimetric
If you do not disable black point compensation in step (c), you will
expand the small lightness range of the space you wish to proof into
the higher lightness range of the space in which you are doing the
proofing.
You need to be concerned about a tad more than just minus five in the
b channel to get a proof -:).
Hope this helps