Pages: [1]   Go Down

Author Topic: OBA/OBC Profiling Q.  (Read 189 times)

howardm

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1954
OBA/OBC Profiling Q.
« on: February 04, 2019, 07:23:38 PM »

Hi,

   Other than 'use a paper w/ low/no OBA', do you bother doing a profile (M0 I would think) w/
    the 2nd OBC test (on XRite, you print a sheet of grays and compare to provided references)
    or for normal house display (fairly low UV assumed), just do M2 and call it a day?

  Is the gray chart that i1Profiler generates 'adaptive' in the same way that the Colormunki 2nd page is?

  Is creating the profile w/ M0 but not doing the secondary gray optimization step a reasonable thing?

Doug Gray

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1610
Re: OBA/OBC Profiling Q.
« Reply #1 on: February 05, 2019, 10:53:34 AM »

Hi,

   Other than 'use a paper w/ low/no OBA', do you bother doing a profile (M0 I would think) w/
    the 2nd OBC test (on XRite, you print a sheet of grays and compare to provided references)
    or for normal house display (fairly low UV assumed), just do M2 and call it a day?

  Is the gray chart that i1Profiler generates 'adaptive' in the same way that the Colormunki 2nd page is?

  Is creating the profile w/ M0 but not doing the secondary gray optimization step a reasonable thing?

M0 doesn't really have a specified level of uV but comparing spectra from high OBA between M0,1 and 2 indicates M0 is about 25-30% less uV than M1. Most prints these days are displayed with very little uV so most all prints I make are with M2 profiles. Even prints on high OBA paper.

Because of the wide variance in those display illuminants that do have uV, XRite has a separate process to adjust profiles for the actual level of uV by comparing various gray patches against those printed when viewed under the illuminant the print will ultimately be displayed with.

Effectively, this creates an adjusted uV response based on the actual uV content of the illuminant and paper OBA.

The second pass in ColorMunki processes is designed to print additional colors where the initial set shows a need to fill in colors to improve profile accuracy. It's unrelated to the uV issue.
Logged

GWGill

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 502
  • Author of ArgyllCMS & ArgyllPRO ColorMeter
    • ArgyllCMS
Re: OBA/OBC Profiling Q.
« Reply #2 on: February 05, 2019, 08:51:00 PM »

Because of the wide variance in those display illuminants that do have uV, XRite has a separate process to adjust profiles for the actual level of uV by comparing various gray patches against those printed when viewed under the illuminant the print will ultimately be displayed with.
Note that I created an alternative approach with similar results in ArgyllCMS.
Logged

Doug Gray

  • Sr. Member
  • ****
  • Offline Offline
  • Posts: 1610
Re: OBA/OBC Profiling Q.
« Reply #3 on: February 05, 2019, 09:48:30 PM »

Note that I created an alternative approach with similar results in ArgyllCMS.
Noted. And it's pretty good too.
Logged
Pages: [1]   Go Up