0 Replies Latest reply: Oct 31, 2008 12:39 AM by SimonTindemans RSS

    Intelligent black point compensation (printing with rel.col. intent)

    SimonTindemans Community Member
      When printing from Lightroom with relative colorimetric intent, black point compensation is always implicitly enabled. This makes sense for most images, as they tend to exceed the dynamic range of the print and the shadows are brightened a bit to keep them from blocking up. However, when the dynamic range of the image *does* match that of the paper, black point compensation is *not* wanted: it reduces the dynamic range of the print for no gain.

      I'm not asking for a return of the black point compensation toggle that is confusing to many people. In keeping with Lightroom's keep-it-simple approach, I think Lightroom should implement an intelligent black point compensation algorithm for use with the relative colorimetric intent. This would work as follows.
      1) The program scans for the darkest pixel (or pixels) in the image. This sets the image black point B_i.
      2) If B_i is lighter than the paper/output black point B_p, print it *without* compensation.
      3) If B_i is darker than B_p, compensate the black point such that B_i is mapped onto B_p. This applies just the right amount of compensation. [currently, 0 is always mapped onto B_p]

      This process would be equal to the current printing procedure if any black pixel is present in the photo. However, it would improve the printing of images without deep blacks. And best of all, this process would require no user intervention, so no interface clutter.

      I hope the team will also see the value of this feature.

      Simon