On 10 Nov 2005, at 11:15, Andy Psarianos wrote:
I have tried to reproduce this blue/purple problem a
few times now and
have been unable to reproduce
Hi Andy.
Make Adobe RGB file (or sRGB if you prefer) .Fill with LAB reference
30,68,-112.
Preview with ISO coated in relative and perceptual modes. See the
difference in hue (hopefully!)
Prior mails may have mentioned colours that are not real. We shoot
flowers that fluoresce into ultra violet and infra red, products with
spot colour , fluorescent backgrounds etc etc. We know that we don't
stand a chance of matching these colours in CMYK , but a good profie
will give a good first stab at it without shjfting the hue too much
.Ir's mostlly at the cost of saturation.
The ECI profiles seem to lose saturation with perceptual colorimetric
rendering intent , and shift hue in saturated blues with relative
colorimetric intent. Building profiles with the FOGRA data using
Profiemaker 5 is giving us better results, and building profiles with
the same software using our own data does likewise.
BTW we proof to ISO standards and get the same results , so it's
apparently not a screen thing.
Hope this helps.
Regards,
Bob Marchant.