5 Replies Latest reply on Jul 7, 2010 2:46 PM by GozerTheGozarian

    Interlace-like banding in ACR6.1 vs. ACR4.6

    GozerTheGozarian Level 1

      I am experiencing interlace-like banding when sharpening images with ACR 6.1. This may be a phenomenon which occurred sometime between ACR 4.6 and ACR 6.1, but I made the jump directly from CS3 to CS5 and so I would not be able to narrow it down any more than that.

       

      Here's what I'm experiencing in a nutshell:

       

      1) If I open up RAW files shot on my Rebel XT, I can sharpen them fine without the banding in ACR 6.1.
      2) If I open up .DNG files shot on my 5D Mark II, they sharpen fine in ACR 4.6.

       

      3) If I open up .DNG files shot on my 5D Mark II, they produce banding in ACR 6.1.
      4) If I open up RAW files shot on my 5D Mark II, sharpening produces the banding in ACR 6.1.

       

      Here are two examples: (This shot isn't the quintessential example, but it was readily accessible. The phenomenon is most pronouned in the palm trees.)

       

      Example One:

      Canon 5D Mark II DNG (Shot in sRAW1 & Zoomed to 100%) with 150 sharpening applied in ACR 4.6

       

      This image is copyrighted by the owner

       

       

      Example Two:

      Canon 5D Mark II DNG (Shot in sRAW1 & Zoomed to 100%) with 150 sharpening applied in ACR 6.1

       

      This image is copyrighted by the owner

       


      Any help would be greatly appreciated. Since ACR 4.6 cannot open raw files from the 5D Mark II, both of these images were obtained from a DNG conversion of the original RAW file. Sharpening of the RAW file in ACR 6.1 produces identical banding.

       


      Thanks,

       

      Dave

        • 1. Re: Interlace-like banding in ACR6.1 vs. ACR4.6
          ssprengel Adobe Community Professional & MVP

          I don't see any detail at all in the Palm Trees.  There is a little stair-stepping along the car window border.  Are you saving the example JPGs with too-high a compression?  You might also resize up by 2x to make the details more obvious and save at the highest-quality.

           

          Otherwise, if I remember, sRAW is not RAW but already a demosaiced TIF created by the camera.

           

          If ACR has a way to change between Process 2003 and Process 2010 then try that to see if the ACR 6.1 photos appear more ACR 4.6-like.

          • 2. Re: Interlace-like banding in ACR6.1 vs. ACR4.6
            Level 7

            There seems to be demosaicing errors in the bright green areas - visible in the palm trees as even/odd lines.

            It's also visible in some of the pine trees.

            • 3. Re: Interlace-like banding in ACR6.1 vs. ACR4.6
              ssprengel Adobe Community Professional & MVP

              Ok, if I zoom in to 300%+ in FireFox on my 1600x1200 monitor I can see the lines.  This could be a result of the new noise/detail processing in LR2.7/ACR5.7 but without more tests it is not possible to say if this is a result of the camera doing something when creating the sRAW which is just an already demosaiced TIF, or if it is happening with all the images from the camera.   I'd suggest trying a full RAW file and see if the banding is there.  Since LR is not demosaicing an sRAW there is less blame for it than there would be for full RAW. 

               

              Pre-ACR 5.7 would be using a much less detailed sharpening and noise-reduction algorithm which could be why you don't see the banding in the ACR 4.6 processing.

               

              I still suggest trying both Process 2003 and Process 2010 to see if it makes a difference, as well as fiddling with the Detail and Contrast and sharpen-masking sliders to see if you can reduce or eliminate the banding.

              1 person found this helpful
              • 4. Re: Interlace-like banding in ACR6.1 vs. ACR4.6
                dorin_nicolaescu Level 5

                From the numerous posts in this forum, it seems that this is a sRaw/mRaw (which is, by the way, not that raw) problem, not ACR's.

                 

                The reason you didn't see them in ACR 4.6 is a different sharpening algorithm, which was not able to extract that super-fine detail.

                 

                Shoot "real" RAW to avoid stair-stepping.

                • 5. Re: Interlace-like banding in ACR6.1 vs. ACR4.6
                  GozerTheGozarian Level 1

                  Process 2003 is a handy workaround, thanks!

                   

                  It is true that shooting in full RAW yeilds better results, but at 2-3 times the filesize, often it doesn't make sense to have a 21 megapixel image when an 8-9 megapixel image will do. (Especially when one is shooting HDR and often taking 9 exposures of the same shot.) But having the workaround is a nice bit of insight.

                   

                  Dave