Andrew Rodney

Andrew Rodney

Santa Fe, New Mexico

Photography background: Corporate Annual Report and Advertising photography specializing in people. Clients included Apple, GTE, Forbes, Microsoft, Smart and Final, Disney, Mrs Gooch’s. Andrew is owner of The Digital Dog, a digital imaging trainin...
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  • Andrew Rodney
    Andrew Rodney
    Participant
    Posts: 294
    Why is there BPC but no WPC?
    on: September 24, 2022 at 12:42 pm

    The ICC doesn’t control or dictate how a CMM operates; they vary, and not all are created equally. This is why Photoshop allows us to switch among them (although doing so may not be in your best interest). ACE has BPC, and the ICC is clear on how it works and why and their recommendations:

    https://www.color.org/WP40-Black_Point_Compensation_2010-07-27.pdf

    9. Recommendations

    In the light of these considerations, the following recommendations appear reasonable for the use of BPC in ICC systems. These systems are of several different types and are intended for different users. For instance, ICC color management can be embedded in the hardware of a printing system serving
    a community of naive users, or it can be provided in an interactive environment for the use of highly 
    expert practitioners. Only the designers of these systems can make the actual choices, but here are some things for them to bear in mind:

    • BPC makes an important contribution to the ICC workflow and can be implemented with minimal change to existing color architectures. It adds value that many users have come to depend on, particularly for Relative Colorimetric RI, which has little value without BPC. This is particularly important for proofing.
    • It should be available for Perceptual and Saturation RIs as well, since it can correct problems presented by certain atypical profiles and is otherwise harmless.
    • In non-interactive environments, where the user has no direct control over this option, BPC should be activated by default. Even in interactive environments, it may be appropriate to activate BPC by default, depending on the sophistication of the intended user community.

    Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

    Andrew Rodney
    Andrew Rodney
    Participant
    Posts: 294
    Re: Monterey 12.6 Update May Break Printing Colour Management & Communication
    Reply #1 on: September 24, 2022 at 11:59 am

    No issues with 12.6 and a VERY old 3880, either printing or with color management. Not an M1 FWIW.

    The output exactly matches printed from Photoshop to that printed out of Lightroom Classic.

    Do not use 16-bit check box; broken as it was in the past and doesn’t do anything useful when it wasn’t broken.

    Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

    Andrew Rodney
    Andrew Rodney
    Participant
    Posts: 294
    Re: Why is there BPC but no WPC?
    Reply #2 on: September 18, 2022 at 9:23 am

    BPC again is SOURCE to DESTINATION! Soft Proofing is a different destination.

    Read the page again. Consider what black on a display represents and ink back represents. Ditto for white.

    The key to understanding this is also the word “compensation”.

     

    Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

    Andrew Rodney
    Andrew Rodney
    Participant
    Posts: 294
    Re: Why is there BPC but no WPC?
    Reply #3 on: September 16, 2022 at 5:50 am

    Life is simple!

    There seems to be some perverse human characteristic that likes to make easy things difficult.” -Warren Buffett

    Keep the darn checkbox on and go forward! It either fixes a rare issue in some problem profiles or does nothing because they map black correctly.

    Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)

    Andrew Rodney
    Andrew Rodney
    Participant
    Posts: 294
    Re: Why is there BPC but no WPC?
    Reply #4 on: September 11, 2022 at 7:13 pm

    No, it wouldn’t be correct.

    http://digitaldog.net/files/Black_Point_Compensation.pdf

    Author “Color Management for Photographers" & "Photoshop CC Color Management" (pluralsight.com)