18 Replies Latest reply on Apr 19, 2009 11:27 AM by Ramón G Castañeda

    ACR color difference with PS CS4

      I tried a search and can't find a thread about what I'm seeing, so I'm posting in the hopes that others may be seeing the same thing.

       

      I have PS CS4 and ACR 5.3 (latest patches) on a Windows XP Pro computer.  I use Adobe RGB as my working space and profile my dual monitors with an Eye One Display2.  I recently started experimenting with using ACR to edit tif files, but I noticed that while the image is loaded in the ACR window it looks quite different color wise than the Bridge thumbnail or within CS4 (after opening it as a smart object).  The look in ACR is similar to what the same image looks like in CS4 with the ColorMatch profile assigned to the image (i.e. quite a bit brighter and lacking saturation).

       

      Here's the weird things:

      • When I first open the tif image, it looks correct as long as the exclaimation mark is present on the preview window.  Once the file is fully processed and that icon disappears the image color makes the dramatic change.  If I then make no changes and simply open the image in CS4, then it's back to the original "correct" colors.
      • If I zoom in the ACR preview to 50% or higher, then the color difference is negligible if not entirely gone, but I can't edit an 8000x5000 without seeing the entire image.

       

      Here's what I have tried:

      • Turned off all OpenGL features
      • Verified my monitor profile was being recognized by CS4
      • Ensured my color settings didn't get changed (preserve profiles is on, as well as ask on mismatch)
      • Tested them with an image that was a known mismatch and it asked what I should do as expected
      • I tried PS CS3 and ACR 4.x with the same result
      • Stripped out XMP metadata with Exiftool to see if that may have been an issue - it wasn't

       

      I'm hoping someone else has an idea what is causing this or if it's a known issue.  Any ideas or confirmation on what I'm seeing would be appreciated.

       

      Craig

        • 1. Re: ACR color difference with PS CS4
          xbytor2 Level 4

          I'm not sure how ACR handles tiffs, but you may want to try this.

          Load the tiff into CS4 and convert it to ProPhoto.

          Compare that with what you're seeing in ACR with the original.

          I suspect that they'll be very very close.

          • 2. Re: ACR color difference with PS CS4
            Level 1

            Thanks for the suggestion, but converting to ProPhoto didn't change the result, I still get the weird color shift.  I have uploaded two screen captures of ACR as it goes through this change.  The image is a scanned tiff image in the ProPhoto color space and the ACR settings are all zeroed on all tabs except for the tint = -5.  I tripled checked that all settings were zeroed as I thought for sure I missed something along the way.  You will also notice that the histogram shifts up in the image that changes color and saturation.

             

            The image in "acr before color change.jpg" matches the image when it's in PS CS4 and the thumbnail/preview images in Bridge, but ACR only stays that way for a few seconds as it loads the image.

             

            I hope this helps to explain what I'm seeing.

            • 3. Re: ACR color difference with PS CS4
              xbytor2 Level 4

              but ACR only stays that way for a few seconds as it loads the image.

               

              This is happening because ACR is initially displaying the preview while it renders the image. When the rendering is complete, the ACR version of the image is displayed.

              I'll check your attachements later after they've popped out of the queue.

              • 4. Re: ACR color difference with PS CS4
                Level 1

                xbytor2,

                I agree about ACR displaying the preview while the exclamation mark is present, but I expect the preview and final rendered image (after the icon goes away) to be identical.  Since this tiff file was created in PS CS4, the embedded preview and image data should be identical.  I think the display of the data within ACR is just messed up in some way, since once ACR transfers the image to CS4 it looks correct again.  This obviously isn't ideal because an incorrect view of the image makes editing near impossible.

                 

                I see my uploaded images are still showing as queued.  How long does it take for them to be viewable?

                 

                Craig

                • 6. Re: ACR color difference with PS CS4
                  xbytor2 Level 4

                  Maybe Eric or Tom or someone else will chime in and explain what's happening when a tiff or jpeg is loaded into ACR. It sounds like it may be more than a simple color profile mismatch problem in this case.

                  I'll try and do some testing of my own later today.

                   

                  Not sure why the image got queued up. There is apparently a way of inserting the image inline rather than as an attachement that avoids using the queue but I haven't tried to do either yet.

                  • 7. Re: ACR color difference with PS CS4
                    Ramón G Castañeda Level 4

                    cssadobe wrote:


                    I see my uploaded images are still showing as queued.  How long does it take for them to be viewable?

                     

                    Craig

                     

                    Craig,

                     

                    Don't send images as attachments—ever.  Use the camera icon in the formatting bar to embed them in your post itself, that way they will appear instantly without getting in the queue to be virus-scanned.

                     

                    Camera-icon-in-reply-box.jpg

                    • 8. Re: ACR color difference with PS CS4
                      Level 1

                      Ok, here are the two images embedded.  It's not nearly as noticable in these very small images, but I think you may get the idea.

                       

                      Craig

                       

                      arc before color change.jpg

                      acr after color change.jpg

                      • 9. Re: ACR color difference with PS CS4
                        Ramón G Castañeda Level 4

                        cssadobe wrote:

                         

                        but I expect the preview and final rendered image (after the icon goes away) to be identical.

                         

                        Why?  The source is different in each instance.  What you are seeing while the yellow alert triangle is shown is a display of the preview that is embedded in the TIFF.  Then ACR build its own rendering based on what's in the full TIFF image itself, not its embedded low-resolution preview.

                         

                        In your examples, there's substantial clipping in the shadows of the blue channel in the embedded preview in the file, but in the ACR rendering the clipping in the blue channel is minimal.  The highlights are heavily clipped in the red channel in both.

                         

                        Maybe I'm misconstruing your posts.  

                        • 10. Re: ACR color difference with PS CS4
                          Ramón G Castañeda Level 4

                          In addition:

                           

                          cssadobe wrote:

                           

                          The image is a scanned tiff image in the ProPhoto color space

                           

                          The scan file may well be in ProPhoto RGB, but you have ACR set to render the image in Adobe RGB.  You're squeezing the original image colors into a narrower, smaller color space in ACR.

                           

                          aaaaaaaaaaaaaa.jpg

                          • 11. Re: ACR color difference with PS CS4
                            Level 1

                            Ramon, thanks for looking.  I was changing settings in an attempt to fix this issue and simply performed the screen captures when I had Adobe RGB set in ACR.  It doesn't matter which space is set, the display of the image is always the same in ACR.

                             

                            A few points of interest:

                            • Since PS CS4 created the tiff, the preview and the actual image data should be identical in my opinion.  Would you agree with that? I don't know why PS would create a preview that was not identical in display characteristics to the actual image.  I can understand raw file previews being significantly different, but not a tiff created in PS.  Maybe I misunderstood your point.
                              • The embedded preview is what the image looks like once imported into PS CS4, Bridge and printed.  ACR is the only application that isn't displaying it in an identical fashion.
                              • The ACR displayed imaged is similar to assigning the ColorMatch profile to the image in PS CS4, but not quite as drastic.    
                              • If I zoom in on the image in ACR to at least 50%, then the difference seems to disappear.  Could this be an ACR anti-aliasing issue when fit-to-screen is used?  However, making overall image changes while looking at a zoomed in image isn't really feasible.   
                              • Since the ACR image display is not identical to what ends up in PS CS4, the only way to edit these tiff images is with trial and error.
                                                    

                              To alleviate your concern that the space may be the source of the problem, I performed another screen capture with ProPhoto as the space.  The histogram changes as expected, but the ACR displayed image is identical:

                               

                              acr after color change prophoto.jpg

                               

                              Thanks again, Craig

                              • 12. Re: ACR color difference with PS CS4
                                Ramón G Castañeda Level 4

                                cssadobe wrote:

                                 

                                  It doesn't matter which space is set, the display of the image is always the same in ACR.

                                 

                                Holy cow!  If that's the case in your setup, you have a HUGE problem, Craig.

                                 

                                You should definitely see a big difference in the ACR preview when you set your ACR worflow options to ProPhoto RGB compared to either Adobe RGB or sRGB.  If you don't, either your monitor is not accurately calibrated and profiled, or it's a lousy narrow-gamut monitor, or your color management is broken.

                                 

                                EDIT:  It could be that the scan was not really made in ProPhoto RGB but was converted by the lab to that profile, in which case then, yes, you would see no difference because the true, original color space was and remains narrower and smaller than the lowest common denominator, which could well be anything, including Color Match or sRGB (and we all know what the s stands for in sRGB!).


                                 

                                cssadobe wrote:

                                 

                                • Since PS CS4 created the tiff, the preview and the actual image data should be identical in my opinion.  Would you agree with that? I don't know why PS would create a preview that was not identical in display characteristics to the actual image.

                                 

                                No, I would not agree with that.  No reasonable person can expect a low-resolution, JPEG-like preview embedded in the TIFF to look identical to the TIFF.  Information has to be discarded to generate the preview.  But that's beyond the scope of ACR.

                                 

                                What I would expect is that ACR would render a better display from the original data in the TIFF than what the mediocre embedded preview can generate.

                                 

                                 

                                cssadobe wrote:

                                 

                                • If I zoom in on the image in ACR to at least 50%, then the difference seems to disappear. 

                                 

                                Well, duh!  You only see the real image when you view it at 100%.  The farther you get from 100%, the more information is either being discarded (at anything less than 100%)  or made up, invented at greater than 100%.  50% is still not as good as 100%, but it's definitely better than the miserably low 8.7% view you were using when you made that last screen shot.

                                 

                                Seeing that you have severe problems with your display, as suggested by the first paragraph in this post, there seems to be no point in discussing in detail any of the discrepancies you mention, most especially at any other view that is not actual pixels (100%).

                                 

                                I'll have to read the thread again when I have the time to see if you have said when you calibrated your monitor last and how, what your color settings are, what monitors you're running, etc.

                                 

                                I validate the calibration on my monitors practically on a daily basis with a hardware calibrator puck.

                                 

                                But, ultimately, viewing a large scan at a dismal 8.7% you can't make any of the judgments you are trying to make.

                                • 13. Re: ACR color difference with PS CS4
                                  Ramón G Castañeda Level 4

                                  In any event, do not expect to have anywhere the latitude and flexibility when running a TIFF through ACR that you would have with a genuine, digital raw file in ACR—not in a million years.

                                  • 14. Re: ACR color difference with PS CS4
                                    Level 1

                                    Ramón G Castañeda wrote:

                                     

                                     

                                    cssadobe wrote:

                                     

                                    • If I zoom in on the image in ACR to at least 50%, then the difference seems to disappear. 

                                     

                                    Well, duh!  You only see the real image when you view it at 100%.  The farther you get from 100%, the more information is either being discarded (at anything less than 100%)  or made up, invented at greater than 100%.  50% is still not as good as 100%, but it's definitely better than the miserably low 8.7% view you were using when you made that last screen shot.

                                     

                                    Seeing that you have severe problems with your display, as suggested by the first paragraph in this post, there seems to be no point in discussing in detail any of the discrepancies you mention, most especially at any other view that is not actual pixels (100%).

                                     

                                    I'll have to read the thread again when I have the time to see if you have said when you calibrated your monitor last and how, what your color settings are, what monitors you're running, etc.

                                     

                                    I validate the calibration on my monitors practically on a daily basis with a hardware calibrator puck.

                                     

                                    But, ultimately, viewing a large scan at a dismal 8.7% you can't make any of the judgments you are trying to make.


                                    Hmm, I beg to differ on this.  PS has no issues with displaying the image correctly at any zoom level.  If I can't get an accurate view of an image at anything other than 100% ACR how do you suggest I make global edits on any file, pan around constantly?  Even a 5 year old digital camera generates files way bigger than a monitor screen.  In any case it's only tiff files that have this issue, so I guess I'll chalk it up to a bug in ACR and move on.

                                     

                                    Sorry to have bothered anyone.

                                    Craig

                                    • 15. Re: ACR color difference with PS CS4
                                      Ramón G Castañeda Level 4

                                      Even in Photoshop, you are only seeing the true image at 100%.  At any other size, Photoshop is either discarding pixels or making them up.

                                      • 16. Re: ACR color difference with PS CS4
                                        Ramón G Castañeda Level 4

                                        Craig,

                                         

                                        This will be just a brief addendum to my last post.  The disgusting slow performance, navigation idiosyncrasies and general un-usability of this new, miserable and ugly forum format, has slowed all contributors down to where some of the regulars are not posting any more, and even the more determined regulars like me have been slowed down to a crawl.

                                         

                                        Since the changeover two weeks ago, we have yet to see a new post here by Thomas Knoll  , creator of both Photoshop and ACR, or by Jeff Schewe  , who wrote

                                        THE book on Camera Raw.

                                         

                                        This afternoon I had been trying to reply to your last post for over twenty minutes before I was able to get back in, but by the time I finally got to the reply box I had to leave with my wife and grandson to get some dinner.  Normally, I would have replied in greater detail, but since even the search function leaves much to be desired, I was unable to fetch links to some of the many, many existing threads on this very same subject where lengthy explanations have been given.

                                         

                                        If you are still interested and determined enough, you may want to browse some of the existing threads.

                                         

                                        You haven't "bothered" anyone.

                                        • 17. Re: ACR color difference with PS CS4
                                          xbytor2 Level 4

                                          Ramón,

                                              With Tom et. al. not here (presumably because of either the 'New & Improved' forum UI or the lack of an NNTP gateway) where can one go to get a camera-raw-tech fix? Is there some invite-only site for the cognoscenti?

                                           

                                          I just received Jeff's new book in the mail. That will keep me occupied until Adobe notices the severe drop off in traffic in some of these groups and does something about it.

                                          • 18. Re: ACR color difference with PS CS4
                                            Ramón G Castañeda Level 4

                                            Well, I haven't checked lately, but Jeff used to be active in the Luminous Landscape forums…