12 Replies Latest reply on May 14, 2012 7:35 AM by Yammer

    ACR 6.7 Colour litter

    Eireannsg1 Level 1

      I have two snippets of a photo taken as RAW format and as JPG.

      The photo taken in Raw format shows colour litter. green tint on the right side of objects and red tint on the left side while in the JPG file everything is OK.

      Does that have to do with ACR or is it a camera flaw? I am using Nikon D800.

      RAWbloop_36.jpg

       

      JPG bloop_37.jpg

        • 1. Re: ACR 6.7 Colour litter
          Eireannsg1 Level 1

          I think its an Adobe camera RAW issue because with the NIkon RAW file viewer the imake looks like that:

           

          bloop_37.jpg

          • 2. Re: ACR 6.7 Colour litter
            Level 5

            That's called CA or Chromatic Aberration, caused by the lens.

             

            The JPEG generated in camera has the Nikon profile for that particular lens already applied to the image in order to correct the CA.  The same CA correction is applied by the Nikon software, so the Color Aberration fringing is corrected.

             

            As has been explained earlier, Camera Raw does not apply any such correction unless you yourself have installed the specific profile for that particular lens and direct Camera Raw to apply the profile correction to your image.

             

            What you are seeing is normal and expected.

            1 person found this helpful
            • 3. Re: ACR 6.7 Colour litter
              Eireannsg1 Level 1

              Thanks for the explanation.

              Interestingly this is the first time I have observed that with Adobe camera raw and only with my D800.

              I have used a Fuji Finepix 550EXR and that doesnt show this effect in its RAW images

              and my old D50 also doesnt give me that kind of chromatic aberration ...with none of my old lenses.

               

              Maybe the camera is just too sensitive

              Or my Nikkor AF-S Nikkor 24-70mm f/2.8G ED must be especially bad when it comes to chromatic aberration....acc to DXOmark its 32µm which sounds like a lot.

              • 4. Re: ACR 6.7 Colour litter
                dorin_nicolaescu Level 5

                So did you turn on CA removal or not?

                • 5. Re: ACR 6.7 Colour litter
                  Level 5

                  I'm also curious to know whether you instructed Camera Raw to apply CA Correction or not.

                   

                  Personally, I absolutely blame the lens. 

                  • 6. Re: ACR 6.7 Colour litter
                    Yammer Level 4

                    It's lateral chromatic aberration (complimentary colours on each side of high contrast objects towards the edge of the photo). You need to switch on Chromatic Aberration Correction in the Lens Corrections tab. I have it set on by default (Save New Camera Raw Defaults).

                     

                    It's not handled by Lens Profiles any more, since 6.7RC, it's done automatically in software, on an image-by-image basis. Hallelujah.

                     

                    If it's already switched on, then you have a problem lens, or CR is confused, but it's not switched on by default, IIRC, so it's worth checking.

                    • 7. Re: ACR 6.7 Colour litter
                      Level 5

                      Yammer P wrote:

                       

                      …Chromatic Aberration Correction…

                       

                      It's not handled by Lens Profiles any more, since 6.7RC, it's done automatically in software, on an image-by-image basis…

                       

                      Thanks for that very pertinent clarification.

                      • 8. Re: ACR 6.7 Colour litter
                        Eireannsg1 Level 1

                        Yes, I have turned it on now. Maybe I havent noticed it because I have just "upgraded" to ACR 6.7 and if Yammer P tells me that in the past versions you didnt have to turn it on then that might have been the problem.
                        Still, I have compared the CA of my new Nikkor AF-S Nikkor 24-70mm f/2.8G ED with the CA of other lenses. It seems the CA of my new lens is the worst compared to all other lenses, 32µm.

                        I compared the values given by DXOmark.

                        • 9. Re: ACR 6.7 Colour litter
                          Noel Carboni Level 7

                          There's an open thread in which we have been discussing that the latest implementation of CA correction isn't as effective as its predecessor.

                           

                          http://forums.adobe.com/thread/1002680?tstart=0

                           

                          -Noel

                          • 10. Re: ACR 6.7 Colour litter
                            Yammer Level 4

                            Regardless of what DxO says, I have 6 Nikon lenses, with my 24-70mm being by far the most expensive and highly-regarded. Despite that, it consistently gave the one of the worst CA-corrected performances of them all in ACR6 versions prior to 6.7, with significant fine-tuning being required in most cases. Now, in ACR 6.7 it is MUCH better.

                             

                            According to Adobe employees in this forum, the problem may have been due to manufacturing tolerances (i.e. my copy is quite different to Adobe's copy) but this seems hard to swallow when it's such a top-end lens. Anyway, I'm very happy now.

                             

                            And, just to clarify, the new setting's Default is Off. If you want it On, you have to set it yourself. Old CA adjustment values are deleted from XMP.

                            • 11. Re: ACR 6.7 Colour litter
                              Eireannsg1 Level 1

                              I have got 5 Nikon lenses and one Tamron lens with the 24-70, being highly regarded, but giving me the worst CA performance.

                               

                              Nikon Asia wrote to me:

                               

                              "our NIKKOR AF-S Nikkor 24-70mm f/2.8G ED lens consists of Extra-low Dispersion (ED) glass elements to effectively reduce the chromatic aberration effect in images"

                               

                              Intersting that the CA is so much worse with this 24-70mm lens than with my other lenses.

                               

                              OK, got it now with that tick box which in previous versions of ACR didnt have to be ticked.

                              Yammer P: Versions before 6.7 didnt have any D800 support. So here we cant say that the 6.7 version is much better than previous versions.

                              • 12. Re: ACR 6.7 Colour litter
                                Yammer Level 4

                                Eireannsg1 wrote:

                                 

                                Yammer P: Versions before 6.7 didnt have any D800 support. So here we cant say that the 6.7 version is much better than previous versions.

                                True, but I don't think the camera has much impact on raw chromatic aberration (if any). It's more of a function of the lens optics and the sensor dimensions.