20 Replies Latest reply on Apr 29, 2015 11:25 AM by trshaner

    Wrong RGB values when soft proofing

    Tukler

      After updating to Lightroom CC, I get the wrong values of the RGB readout under the histogram when soft proofing.

      Example: An RGB value that should read 255,0,0 adobe RGB reads 189,35,6

      The image, display just fine as a soft proof.

       

      Camera raw displays the right values and so does Lightroom 5.7.1

       

      I'm running Windows 8.1 and my laptop with Windows 7 show the same error

       

      Is this a bug?

       

      Kind regards

      Anders Tukler

        • 1. Re: Wrong RGB values when soft proofing
          trshaner Adobe Community Professional & MVP

          I suggest posting two screenshots showing the area you are measuring 255,0,0 and in Soft Proof mode 189,35,6. What color profile is being selected in the Soft Proofing panel?

          • 2. Re: Wrong RGB values when soft proofing
            Tukler Level 1

            To find out whats going on I've made an image in Photoshop with different coloured patches.

            I've created several images with different working spaces, ProPhoto RGB, Adobe RGB and sRGB. 8-bit and 16-bit. They all measure wrong in Lightroom's Soft Proofing.

            This screen capture uses Adobe RGB and is a 8-bit TIFF-file. The Cursor is over the red patch and it reads it values correctly to 87,6%, 40,7%, 16,7%.

            standard.gif

            When I turn on Soft Proofing with Adobe RGB and hover the cursor over the red patch the values reads 189,35,6.

            softproof.gif

            This is what I get for all the patches:

            255,0,0 = 189,35,6

            0,255,0 = 29,212,19

            0,0,255 = 37,7,230

            255,255,255 = 255,255,255

            0,0,0 = 0,0,0

            250,250,250 = 244,244,244

            128,128,128 = 56,56,56

            25,25,25 = 2,2,2

            230,200,170 = 183,155,110

            200,150,100 = 124,88,39

             

            From what I can tell, the visual soft proofing works fine, but the values are off.

             

            Cheers

            /Anders

            • 3. Re: Wrong RGB values when soft proofing
              trshaner Adobe Community Professional & MVP

              LR uses the Melissa color space, which is ProPhoto RGB with a Gamma of 1.0. See if this post makes sense concerning the readings:

               

              Split RGB values in Soft Proofing Histogram

              • 4. Re: Wrong RGB values when soft proofing
                thedigitaldog MVP & Adobe Community Professional

                I think the OP is onto something, something is wrong, please see if you can replicate this. Numbers between CC and 5.7 are NOT THE SAME!

                I built a similar image in Adobe RGB and ProPhoto RGB. I imported in LR 5.7 and CC, set the soft proof for ProPhoto RGB. In the screen capture here, I'm selecting the ProPhoto RGB image. AFAIK, all settings are identical, the numbers between each build are not!

                 

                http://digitaldog.net/files/LR5vsCC_numbers.tif

                 

                LR5vsCC_numbers.tif

                • 5. Re: Wrong RGB values when soft proofing
                  thedigitaldog MVP & Adobe Community Professional

                  One more example:

                  LR5vsCC_numbers1.jpg

                  • 6. Re: Wrong RGB values when soft proofing
                    ssprengel Adobe Community Professional & MVP

                    See if you get different numbers with the GPU on and off.

                     

                    If you turn Softproof off are the color numbers the same?  They should be.

                     

                    Also using a TIF for a screenshot is less useful than a PNG or JPG.

                    • 7. Re: Wrong RGB values when soft proofing
                      Tukler Level 1

                      I still get the same error when I disable the GPU acceleration.

                      And the values readings are correct and identical to Lightroom 5.x when soft proof is off.

                      /Anders

                      • 8. Re: Wrong RGB values when soft proofing
                        Tukler Level 1

                        trshaner skrev:

                         

                        LR uses the Melissa color space, which is ProPhoto RGB with a Gamma of 1.0. See if this post makes sense concerning the readings:

                         

                        Split RGB values in Soft Proofing Histogram

                        Thanks! Now I know whats going on!

                        When I applied a ProPhoto RGB profile with a gamma of 1.0, I get the exact same values in in Photoshop as in Lightroom CC.

                        This must be a bug!

                        When we soft proof an image in Lightroom we should get the RGB readout of the profile applied.

                         

                        Question:

                        Do some of you get the correct values? Is this a Mac/PC thing?

                        /Anders

                        • 9. Re: Wrong RGB values when soft proofing
                          sandy_mc Level 3

                          Yes, that's gamma 1 (LR 6) vs gamma 1.8 (LR5). Maybe a bug. Or a "feature". BTW, Melissa is generally considered to be ProPhoto primaries plus an sRGB "gamma", not that it makes any difference.

                          • 10. Re: Wrong RGB values when soft proofing
                            Tukler Level 1

                            sandy_mc skrev:

                             

                            Yes, that's gamma 1 (LR 6) vs gamma 1.8 (LR5). Maybe a bug. Or a "feature"

                            I'm not sure I like it as a feature.

                            Lightroom 5 gave us the choice of displaying values in different profiles (eg sRGB, Adobe RGB and even a non standard ProPhoto RGB with gamma 1.0)

                            It's like we're back in the USSR. :-)

                            /Anders

                            • 11. Re: Wrong RGB values when soft proofing
                              trshaner Adobe Community Professional & MVP

                              thedigitaldog wrote:

                               

                              I think the OP is onto something, something is wrong, please see if you can replicate this. Numbers between CC and 5.7 are NOT THE SAME!

                              Yes, I am seeing a difference between LR5.7.1 and LR CC 2015. I measured the left White patch (244, 244, 239) and right Black patch (39, 39, 40) in Soft Proof mode with Profile = ProPhoto RGB, Perceptual.

                               

                              LR 5.7.7:           244, 244, 239     39, 39, 40

                              PS CC 2014:     244, 244, 239     39, 39, 40

                              LR CC 2015:     236, 236, 227     09, 09, 09

                               

                              If I open the above ProPhoto RGB Macbeth image in PS CC2014 and apply 'Convert To Profile' with a ProPhoto RGB 1.0 Gamma profile the numbers are the same as in LR CC 2015.

                               

                              PS CC 2014:      236, 236, 227     09, 09, 09 (Convert To Profile> ProPhoto RGB 1.0 Gamma)

                               

                              The problem appears to be that LR CC 2015 Soft Proof is showing the RGB values converted to the destination profile, but in the Melissa RGB native color space (ProPhoto RGB Gamma 1.0).

                               

                              The Soft Proof RGB values are the same with 'Use Graphics Processor' both unchecked and checked.


                              • 12. Re: Wrong RGB values when soft proofing
                                thedigitaldog MVP & Adobe Community Professional

                                trshaner wrote:

                                Yes, I am seeing a difference between LR5.7.1 and LR CC 2015. I measured the left White patch (244, 244, 239) and right Black patch (39, 39, 40) in Soft Proof mode with Profile = ProPhoto RGB, Perceptual.

                                Good (well not really). So there's a bug here. I tried again this morning and found with any two identical rendered images using the same soft proof setup, I get differing values between LR5 and LR6.

                                Further, as the OP reports. LR6 is not producing the correct values when soft proofing a document using it's native profile while LR5 is. For example, In the 2nd image I uploaded above, it's in Adobe RGB (1998) and is a TIFF. IF I soft proof using Adobe RGB (1998) one would expect a null transform. The values we get in LR would match what we get in Photoshop. That is the case in LR5 but not LR6.

                                 

                                Going a bit OT, I found what I think is a bug in Photoshop CC with soft proofing. It has to do with the preview not the numbers. If I open a document in Adobe RGB (1998) and soft proof it in that color space, I see the preview update! I don't see that in CS6. Again, if the source color space and the soft proof color space match, we should see no visual difference nor the numbers change. LR6 appears to produce the wrong values, Photoshop the right values and wrong preview, at least on the Mac. Sigh....

                                • 13. Re: Wrong RGB values when soft proofing
                                  trshaner Adobe Community Professional & MVP

                                  thedigitaldog wrote:

                                  Going a bit OT, I found what I think is a bug in Photoshop CC with soft proofing. It has to do with the preview not the numbers. If I open a document in Adobe RGB (1998) and soft proof it in that color space, I see the preview update! I don't see that in CS6. Again, if the source color space and the soft proof color space match, we should see no visual difference nor the numbers change. LR6 appears to produce the wrong values, Photoshop the right values and wrong preview, at least on the Mac. Sigh....

                                  Try changing the GPU settings in PS CC Drawing Mode to 'Normal' or even 'Basic' and see if that's causing the difference. Re: Strange sRGB soft-proofing behavior

                                  • 14. Re: Wrong RGB values when soft proofing
                                    thedigitaldog MVP & Adobe Community Professional

                                    trshaner wrote:

                                    Try changing the GPU settings in PS CC Drawing Mode to 'Normal' or even 'Basic' and see if that's causing the difference. Re: Strange sRGB soft-proofing behavior

                                    Made no difference but I didn't restart PS must I?

                                    • 15. Re: Wrong RGB values when soft proofing
                                      trshaner Adobe Community Professional & MVP

                                      PS application restart is required only, but not a system restart.

                                      • 16. Re: Wrong RGB values when soft proofing
                                        thedigitaldog MVP & Adobe Community Professional

                                        trshaner wrote:

                                         

                                        PS application restart is required only, but not a system restart.

                                        Thanks. Indeed, setting Basic fixes the issue. So it's a bug. Doesn't do this in CS6.

                                        • 17. Re: Wrong RGB values when soft proofing
                                          trshaner Adobe Community Professional & MVP

                                          I'm seeing a soft proof issue on WIndows 7 with both PS CC2014 and PS CS6. Open a ColorChecker image with AdobeRGB profile and set the Proof color profile to Adobe RGB. Using CTRL + Y to toggle soft proof view I see a slight change in the saturation of some of the panels. Obviously there should be no change. What exactly are you seeing in the image with PS CC and then PS CS6 in Normal Drawing Mode?

                                          • 18. Re: Wrong RGB values when soft proofing
                                            thedigitaldog MVP & Adobe Community Professional

                                            trshaner wrote: What exactly are you seeing in the image with PS CC and then PS CS6 in Normal Drawing Mode?

                                            If I set my Mac to Basic for GPU, I see no change toggling soft proof on and off in either. I had Basic set in CS6 so when I was testing it previously, I saw no difference.

                                            So yes, it's an old bug that remains. Thanks.

                                             

                                            Now back to the LR bug which is for real. I used an output profile in both LRCC and LR 5.7. LR5.7 produces the correct values, they match when I actually convert to the output color space in Photoshop. So PS and LR5 are correct. LR6 is producing the wrong values no matter what profile I select in the soft proof.

                                            • 19. Re: Wrong RGB values when soft proofing
                                              trshaner Adobe Community Professional & MVP

                                              I'll post a bug report at the Photoshop Family forum and post the link back here.

                                              • 20. Re: Wrong RGB values when soft proofing
                                                trshaner Adobe Community Professional & MVP

                                                The Problem Report is posted here: Lightroom CC Soft Proof Histogram Displays Incorrect RGB Values Please add your +1 vote and comments. Thank you!