5 Replies Latest reply on Jan 30, 2014 8:21 PM by ssprengel

    Creating profiles for special illuminants in DNG Profile Editor

    blumesan Level 1

      I have successfully used the DNG Profile Editor with images of the ColorChecker Passport to create simple dcp profiles for daylight and tungsten illumination.  I have obtained very satisfactory profiles using both a single image and the "both color tables" option, as well as two images (one tungsten and one daylight) and the "dual illuminant" method.

       

      Now I wish to construct separate profiles for use with unusual light sources: fluorescent lights and white LED lights.  Can some one tell me how this is best done using the DNG Profile Editor.

       

      Appreciate any suggestions.

       

      Mike.

        • 1. Re: Creating profiles for special illuminants in DNG Profile Editor
          ssprengel Adobe Community Professional & MVP

          You can profile other types of lighting the same as you’ve already done, just take a picture of the CC PP in whatever lighting you want to profile for and make a single-illuminant profile.  Call it something that makes sense.

           

          I name my profiles for the camera, the type of lighting and the color temp and tint so I can select which ones are most applicable based on the current image’s WB even if I haven’t profiled specifically for.

           

          For example here are the names of some of my profiles, both the name in LR and the name of the file.  I include the camera name more so I can tell the files apart, since LR will automatically only show me the ones for a particular camera.  Although it haven't with these, it is also useful to indicate the software used to create the profile.  Adobe's or X-Rite's because they produce slightly different profiles and it helps to debug problems with your profiles if you know which software created which one.  I'd probably include an A or a X on the end if I was doing things for a new camera.

           

          300D_2600K+17-6700K-6_Dual.dcp

           

          450D_2100K+15_SodiumVaporStreetlight.dcp

          450D_2600K+8_Valparaiso_Wedding_Stage.dcp

          450D_2700K-6500K.dcp

          450D_3700K+22_Fluorescent.dcp

          450D_5000K.dcp

          450D_7400K+8_ShadeEvening.dcp

          450D_FlashDirect.dcp

           

          7D_3800K+23_BestBuyLighting.dcp

          7D_6300K+16_PopupFlashAtBestBuy.dcp

           

          If you have purchased the CC PP yourself, then there is a Color Profile manager program you can use to enable and disable your profiles so you don't have such a long list in LR if you've made many for different types of lighting.  If I have a one-time profile for a particular venue, I will make sure an copy the profile to the folder with the actual photos in case I want to remove one-time profiles to keep the clutter down a little.

          • 2. Re: Creating profiles for special illuminants in DNG Profile Editor
            blumesan Level 1

            ssprengel,

             

            Many thanks for your response.  I am still not clear what you mean when you say "make a single illuminant profile".  I am aware that there has been some confusion about the terminology relating to the DNG Profile Editor; in particular what is meant by a "single illuminant profile".  As I understand it there are (at least) two ways to proceed when starting with a single image of the CCPP, taken using the appropriate (single) illuminant.  Open the DNG file in the PE.  After selecting the Chart tab one can either:

             

            a) Select the "Both color tables" option and then Create Color Table or

             

            b) Select a color temp from the drop down menu (2800K or 6500K) and then Create Color Table.

             

            Which of these alternatives is best suited to creating a profile for an unusual light source?  In my case the color temperature of the source would most certainly fall in the range between illuminant A and D65 but the spectral profile would be rather spikey and not resemble either tungsten or daylight.  As I understand it, a separate profile for these conditions is the best solution.

            • 3. Re: Creating profiles for special illuminants in DNG Profile Editor
              ssprengel Adobe Community Professional & MVP

              When there are two illuminants in a profile ACR will interpolate an effective profile based on how far the actual image WB is from one of the illuminants in the dual profile.  For example if the profile is using the 2650K (Tungsten) and 6500K (hazy sunight) as the two illuminants and your images is taken in direct sunlight with a WB of 5000K then the profile will be more the D65 profile but a little bit of the redder A profile mixed in.  This allows the dual profile to be used for any lighting with a Temperature between A and D65 that also has a Tint number close to or a little above zero.  An A/D65 dual profile fails for fluorescent lighting because the Tint number is quite a bit different than either the A or D65 Tint numbers.

               

              To your question, for a single illuminant profile, you should use the Both Color Tables option so that no matter what WB your photo has, the profile used will be the same.  This makes the illuminant A and D65 irrelevant because any interpolation between the two illuminants would result in the same profile numbers.

               

              However, I also think that the dual illuminant numbers are not necessarily hard-coded to A and D65, at least not when you use the CCPP plug-in for LR to create the profile, but are actually whatever your photos WB numbers are, so you can make dual-illuminant profiles for other pairs of lighting, such as fluorescent and daylight or fluorescent and incandescent, or even sunlight and shade, depending on what mixed lighting you have at your location and time of day.

               

              An easy way to test this would be to make a dual profile, one DNG being fluorescent and one being your blue LEDs (two sources far away from A or D65), then also create two single profiles, one for each of those same two lighting sources.  Test the dual-illuminant profile with the fluorescent CCPP image, and then switch the profile to the single illuminant fluorescent one and see if anything looks different.  Do the same test with the blue-LED CCPP image with dual and single blue-LED profiles. 

               

              If the look of the image is the same when using a dual profile where one end is the same as the single profile both tested with the actual CCPP image that was used to make the profile or one end of the profile, then the illuminant numbers in the dual profile change to whatever the DNGs illuminants were.  However, if the look changes between the dual profile and the single profile when applied to one of the dual-profiles image's WB then the illuminant numbers must be fixed to A and D65, and so any dual profiles are useless if the two illuminants do not match A and D65.

               

              If your experiment fails using the DNGPE, then try it using the CCPP software and the LR plug-in. 

              • 4. Re: Creating profiles for special illuminants in DNG Profile Editor
                blumesan Level 1

                ssprbgel,

                 

                Again thanks for your reply. 

                 

                When you say "use the CCPP plug-in for LR to create the profile" I am led to believe that you are using the X-Rite software to create your profiles, and your other remarks are applicable to profiles created with software.  The Adobe DNG Profile Editor has no plug-in for LR (nor for ACR).

                 

                In any case, many thanks for your suggestions.

                • 5. Re: Creating profiles for special illuminants in DNG Profile Editor
                  ssprengel Adobe Community Professional & MVP

                  CCPP is sold by x-rite so yes, CCPP plug-in means x-rite’s LR plug-in.