3 Replies Latest reply on Oct 25, 2008 6:50 AM by MadManChan2000

    DNG Profile Editor, a question or a request.

    bokeron2008 Level 1
      I have just played a little bit with it, and a question comes to my mind.

      When you select a color, i.e, RGB 33,26,21, is there a way to edit not only this puntual color but a range of similar tones ?

      Like editing a "field" around the color point selected, and being able to modify how widespread this "field" is or even it's form, and defining a "fallof zone" in wich the changes are applied in a subtler degree ... this would provide a way to define the range of colors affected ...and posiibly prevent posterization.

      So... this is my question. And if the answer is "No"... then make it a request :)

      Now, a direct request. Can a "gamut safeguard" or "gamut indicator" be implemented ?

      This way, we would know if the color change we've just made to the camera profile fits inside a given color space (or not).
      I think this "gamut comparison engine" could be put to different uses, like visually indicating what colors of the current image would fit inside our printer color profile (and therefore would not need conversion),or alerting the user that the last change they've made to the color profile will exceed his screen/printer capabilities of representing it faithfully.

      I guess this might be able to allow the creation of profiles for a given camera that would give users the power to decide in advance how a given color would render when printed.

      Dou you think this is a good/bad idea (or a stupid one) ?
        • 1. Re: DNG Profile Editor, a question or a request.
          MadManChan2000 Adobe Employee
          bokeron, the color control points in the PE currently already have this "range of similar tones" ability. That is, when you create a color control point by clicking somewhere in the image, and you make an adjustment (e.g., decreased saturation), this adjustment affects not only that particular color but a range around it. You can preview this by clicking on an adjustment in the Color List Box and choosing "Show Affected Colors" from the Options menu. You will then see a preview, both in the image and in the color wheel, of which colors are affected.

          The selected color range is defined implicitly by your set of color control points, i.e., as you add more color control points, you will see how the individual color ranges get redistributed, to make sure you get smooth interpolation between the control points. This should be more clear if you try adding a few control points while the Show Affected Colors option is turned on.

          I will think about the 2nd request.
          • 2. Re: DNG Profile Editor, a question or a request.
            bokeron2008 Level 1
            Thanks for your answer, Eric.

            Now that I've been playing with it a bit more it's clear that every color point implies a color range, though I didn't realize the ranges were being readjusted every time a new point is selected (I did not tried "Show Affected Colors" before)

            I think the "auto-selected" ranges are too big. It should help to get smooth transitions (the weird thing is, I've had bad results when trying to increase the blue color saturation ... maybe I increased it too much ?)
            I suppose the auto selected ranges need to be this big to ensure continuity, but when i want to adjust a certain range of skin tone color... every skintone seems to be affected by the change in some degree.

            Another example : Let's say I want to add more saturation to the originally already saturated colors, and only those -- i.e. strong red or blue, to make it even stronger. I can't, because almost every blue gets its saturation increased at the same time.
            Maybe the workaround could be to select a few more color points around my intended one, those colors I don't want to alter, to prevent it. It seems more difficult than necessary for my needs, but I'll try to see if I can make it work that way.
            That's why I asked for selectable ranges. Does it make any sense ? Or maybe the functionality is there, but I'm not used to this approach yet ?

            Now, another thing I've been thinking about. When representing changes in saturation, hue and lightness in the color circle... wouldn't a 3d graph be more convenient to show it ?
            Maybe not really necessary, but I suppose a fully rotable 3d graph would better give us a visual idea of what's happening with every adjustment we make than a 2d circle. Or just keep the circle for simplicity and add the 3d graph as an option.
            This 3d graph would come handy too if the "gamut safeguard" was ever implemented. Nothing like "seeing" if the profile you are tweaking fits into the color space of reference, or not.
            • 3. Re: DNG Profile Editor, a question or a request.
              MadManChan2000 Adobe Employee
              bokeron, this is the idea behind using multiple color control points. As explained in the DNG PE documentation and tutorials, you can use color control points together to localize color corrections. You use one or more points to lock down colors you don't want to change. You use another point to make a specific adjustment (i.e., to colors you DO want to change). It should only require a few clicks to do this.

              Suppose you want to increase blue saturation in a blue sweater but not the blue sky. Click on the blue sky to "pin" it down. Then click on the blue sweater and make an adjustment. That's it: you've adjusted the blue sweater without affecting the sky. The case where this won't work is if the blue sky and blue sweater are actually the same hue & saturation, which means they're the same color and clearly you can't adjust one without adjusting the other. (Profile edits are global across an image, not local.)

              Your second point is really about 2.5D edits versus 3D edits. The DNG Profile Editor only supports 2.5D edits. That is, you can index by hue & saturation (2D) and make adjustments to hue, saturation, and value/luminance (3D). But you cannot make separate adjustments to two colors that have the same hue & saturation, but different values/luminances.