24 Replies Latest reply on Dec 12, 2009 11:52 PM by Almanbrother65

    ACR 5.6 Canon eos 7D compare to DPP

    Almanbrother65 Level 1

      When I open a raw-file from my 7D in ACR 5.6 RC photoshop CS4 the image is almost 1-2 stops darker then when I open the same raw-file in Digital Photo Professional from Canon. This is not advantageous for the grain in the image. I have to adjust the exposure to almost +1-2 stops. Alsoo the image on the lcd-screen of my camera seems to be lighter.

      It happen also in adobe bridge. Do I have to configure bridge for ACR 5.6?

       

      Is this a known issue in ACR 5.6 RC?

       

      Are there more users who have this problem?

       

      Kind regards,

      Aldert

        • 1. Re: ACR 5.6 Canon eos 7D compare to DPP
          Panoholic Level 2

          1. Are you sure, that you are effectively using ACR 5.6? (You may have installed it in the wrong location.)

          Click "Help", "About Plug-In", "Camera raw".

           

          2. Your almost 1-2 stops sounds strange. How much is it?

           

          3. This initial darkness does not affect the "grain"; however, if you are using 5.5, then the noise looks worse.

           

          You are not working with DNG, are you? You wrote I open the same raw-file, this suggests that you are using the CR2 file.

           

          Gabor

          • 2. Re: ACR 5.6 Canon eos 7D compare to DPP
            Myke1954 Level 1

            I recently bought a 7D and updated my copy of Lightroom 2.5 to 2.6RC  (the equivalent of ACR 5.6 RC) on 28-29 Nov.

            I didn't upate my CS4 copy to ACR 5.6RC as I wanted to check the results/performance/stabiliy first.

             

            I have found the same/similar problem with RAW in Lightroom 2.6RC - the exposure is about a stop darker with LR2.6RC than with DPP (or Zoombrowser).  I reported the problem to Adobe on 28 Nov & am awaiting the results.  It is difficult to say exactly what the stop diff is as other parameters (e.g. contrast) appear to be slightly different and you can get closer (match) to the DPP 'view' by varying these as well as exposure. 

             

            I know it not much help, but at least you know that there are other experiencing the same/similar problem. 

             

             

            Regards,

            Myke

            • 3. Re: ACR 5.6 Canon eos 7D compare to DPP
              Panoholic Level 2

              1. Is this "darkening" problem the same with all ISOs, or does it depend on the ISO?

               

              2. Was HTP On?

               

              3. How does it look like with a DNG created by the version 5.6 converter from the CR2?

               

              Gabor

              • 4. Re: ACR 5.6 Canon eos 7D compare to DPP
                PBoehme Level 1

                I have noticed the same issue for my 7D raw images when using the RC version of DNG Converter.  I thought that it was my problem with not setting exposure correctly, but the in-camera histograms dosn't indicate underexposure.  Since it is the only version of DNG Converter installed on my computer there is no confusion about using the wrong file.  I am currently using DNG Converter because I am still using CS3 Extended (and probably will until I can afford to upgrade).  I also see a very slight color bias shift with changes in luminosity.  This effect is very subtle and mainly noticeable only on neutral subjects

                • 5. Re: ACR 5.6 Canon eos 7D compare to DPP
                  Myke1954 Level 1

                  1. Only shot with Iccurs with ISO 100, 200 & 400.  All both within same ISO & across the 3 ISO's appear darker.  The amounts do appear to vary within ISO typicall it around 2/3 of a stop butI find it difficult to be specific as the colours, contrast are also different & for example a higher contrast can at make the image appear darker.   

                   

                  2. HTP was off  (I used all the used all camera C.Fn I, II and III defaults as I recall)

                   

                  3. I've not used DNG.

                   

                  Myke

                  • 6. Re: ACR 5.6 Canon eos 7D compare to DPP
                    Almanbrother65 Level 1

                    @ Gabor: Sure I use ACR 5.6 RC. And when I have to adjust the exposure it is effective on the grain. Same as you take a photo underexposed and you have to adjust your exposure.

                    When I opened a cr2-file in ACr I have, depending on some other facts, adjust the exposure between ~ +1.25-+1.75.

                    That is in my opinion extreme. Just like someone els said: the histogram is oke.

                    I have used iso 100, 200 and 400 and all the same problem.

                    I don't use dng.

                    And what's htp?

                     

                    Aldert

                    • 7. Re: ACR 5.6 Canon eos 7D compare to DPP
                      Panoholic Level 2

                      I converted a 7D image with the DNG converter version 5.5 and with 5.6., and loaded both in ACR, version 4.6 (I don't have CS4).

                      There is some very small difference in the intensities, not uniform; this is not a surprize, as the color conversion matrixes have been replaced in version 5.6. There are some other differences in the DNG files, but they balance each other.

                       

                      Anyway, I uploaded two DNG files, one converted with 5.5, the other with 5.6. The conversion results are very close with ACR 4.6 regarding the intensity. I suggest you to download then (both are about 13 MB) and test if they are displayed with very different intensity in your environment:

                       

                      http://www.panopeeper.com/Download/Canon7D_ISO00100_DNG5.5.dng

                      http://www.panopeeper.com/Download/Canon7D_ISO00100_DNG5.6.dng

                       

                      Aldert: the "grain" (the noise) has been established at shooting. When increasing the intensity (lightness), it becomes more visible in absolute term, of course, but not relative to its surrounding. The noise is often measured in "signal to noise ratio", and that remains the same, no matter how bright the image is displayed.

                       

                      Gabor

                       

                      ADDED: ACR does apply a -0.25 EV "exposure" adjustment to the 7D images (not shown on the slider), but that is far from the 1-2 stops mentioned here.

                      • 8. Re: ACR 5.6 Canon eos 7D compare to DPP
                        Almanbrother65 Level 1

                        Thanks Gabor, i will test is tomorrow because I'm on my work at this moment.

                        I know the brightness doesn't matter to the noise, but when I adjust the exposure in ACR that will effect the noise?

                        In ACR my image seems to be underexposed, and when I adjust the exposure with +1,5 in ACR the noise become more visible, especcially in darker parts of the image (forgive my terrible english).

                         

                        Regards,

                        Aldert

                        • 9. Re: ACR 5.6 Canon eos 7D compare to DPP
                          PBoehme Level 1

                          I am fairly certain that the Brightness slider does affect noise.  Shifting bits upwards will always increase noise.

                          • 10. Re: ACR 5.6 Canon eos 7D compare to DPP
                            Panoholic Level 2
                            function(){return A.apply(null,[this].concat($A(arguments)))}

                            function(){return A.apply(null,[this].concat($A(arguments)))}

                            PBoehme wrote:

                             

                            I am fairly certain that the Brightness slider does affect noise.  Shifting bits upwards will always increase noise.

                             

                            (Forget about "shifting bits")

                             

                            The following four samples are from the very same image. No noise reduction (as far as that is possible with ACR), only the "Brightness" adjustments were different: 150, 100, 50 and 0. Would not you say, that the first, the brightest one is the most noisy? Well, the signal-noise ratio is the highest with the brightest one, i.e. the noise is the lowest in that version, compared to the context.

                             

                            It's easy to try: convert the same image with different exposure or brightness settings, put them as layers over each other, make a selection from a noisy, but uniformly lit, untextured spot and look at the Histogram panel; source: Entire Image, display a layer and divide Mean with Std Dev.

                             

                            SNR_Demo.jpg 

                             

                            Gabor

                            • 11. Re: ACR 5.6 Canon eos 7D compare to DPP
                              Jeff Schewe Level 5

                              PBoehme wrote:

                               

                              I am fairly certain that the Brightness slider does affect noise.  Shifting bits upwards will always increase noise.

                               

                               

                              Actually, no...the ONLY thing increasing brightness does is make the current noise more apparent, it does nothing to "increase" the noise.

                               

                              The noise signature of your sensor is the same at the lowest ISO as it is at the highest IOS...the differences are in the increase of the apparent noise due to increased amplification of the noise due to increased processing of the analogue to digital conversion...

                               

                              The noise is the same, only it's perception (obviousness) is changed...

                              • 12. Re: ACR 5.6 Canon eos 7D compare to DPP
                                Almanbrother65 Level 1

                                And that is what I said: the noise became more visible.

                                @Gabor: I cannot download the files.

                                Can anyone explane what HTP is?

                                 

                                 

                                To be more specific, when I put my cf-card in my cardreader and open bridge, the first look af the thumbnails are with normal exposure, compared with the brightness on my camera-lcd.

                                Then bridge begin to load the data from the cr2-files and the thumbnails are set darker (1-2 stops). And then, when I open the cr2 in ACR photoshop they are as dark as they are in bridge.

                                 

                                I know now what HTP is. HTP is off

                                • 13. Re: ACR 5.6 Canon eos 7D compare to DPP
                                  Panoholic Level 2
                                  function(){return A.apply(null,[this].concat($A(arguments)))}

                                  Jeff Schewe wrote:

                                   

                                   

                                  The noise signature of your sensor is the same at the lowest ISO as it is at the highest IOS...the differences are in the increase of the apparent noise due to increased amplification of the noise due to increased processing of the analogue to digital conversion...

                                   

                                  The noise is the same, only it's perception (obviousness) is changed...


                                  1. The "noise signature" of the camera (of the sensor combined with the electronics on the board) does change with ISO; increasing the ISO increases the signal to noise ratio. I guess you could profit from reading http://www.cryptobola.com/PhotoBola/SourceOfNoise.htm

                                   

                                  2. Increasing the intensity (by "brightness", "exposure", "fill", whatever) does not change the signal to nosie ratio on its own. However, the non-linear mapping (the application of the "gamma curve") reduces the differences between the displayed pixel values with increasing intensity; therefor the signal to noise ratio is increasing with higher intensity (like in the sample I posted above). However, we see the higher intensity better, therefor the noise is more apparent, even though the SNR is greater.

                                   

                                  Gabor

                                  • 14. Re: ACR 5.6 Canon eos 7D compare to DPP
                                    Panoholic Level 2
                                    function(){return A.apply(null,[this].concat($A(arguments)))}

                                    Almanbrother65 wrote:

                                     

                                    I cannot download the files.

                                     

                                    The site is blocked as the moment. Someone or something reported some "malicious content" without specifying, which file, and the service provider blocked everything. I am in the "process of resolution". Sorry for that.

                                     

                                     

                                    Gabor

                                    • 15. Re: ACR 5.6 Canon eos 7D compare to DPP
                                      john cornicello (retired) Level 4

                                      I just did a quick image test with the 7D and opened the same CR2 file in ACR 2.6 and DPP. The DPP image is slightly lighter. For example, the 2nd gray patch in the color checker reads 213/213/213 in DPP and 206/206/206 in ACR.

                                       

                                      Not sure how they'll look after being converted to JPG. I set ACR to "Camera Neutral" because I have the camera set to that and expect that DPP is reading that.

                                       

                                      7d_colorchart.jpg

                                       

                                      If you want a copy of the original raw file (~21 meg file), I uploaded it to YouSendIt and it should be available for 7 days (or 100 downloads)...

                                      https://www.yousendit.com/download/MVNjeFlRQ3RkMnQzZUE9PQ

                                       

                                      John

                                      • 16. Re: ACR 5.6 Canon eos 7D compare to DPP
                                        Panoholic Level 2
                                        function(){return A.apply(null,[this].concat($A(arguments)))}

                                        John Cornicello wrote:

                                         

                                        I just did a quick image test with the 7D and opened the same CR2 file in ACR 2.6 and DPP. The DPP image is slightly lighter. For example, the 2nd gray patch in the color checker reads 213/213/213 in DPP and 206/206/206 in ACR.

                                         

                                         

                                        What adjustment did you have in ACR? I tried it with ACR 4.6 in DNG format, converted by 5.6. I get 202/202/202 on that patch only with Brightness=50; with Brightness=0 (and all other settings 0) it's only 156. DPP shows 214-216. I picked WB on that patch in both converters.

                                         

                                        The 206/206/206 would be very good, because you have to set Exposure to +0.25 to counter the BaselineExposure -0.25 (with ISO 100). The 202/202/202 becomes 213/213/213 with the +0.25.

                                         

                                        Without Brightness, with Exposure only, I need +1.00 to get to 214; this is in effect +0.75 EV, still not "1-2 stop", but certainly much darker than DPP.

                                         

                                        Gabor

                                         

                                        ADDED: your camera has quite strong banding caused by the 8-channel readout (very common for the 7D). Increase the intensity until you see the brownish dark area at the bottom right of the color checker pack in the RGB range 25-40. The raw intensity in this area is in the 9th and 10th stop of the DR, which is supposed to be in the camera's range. You don't see this with DPP.

                                        • 17. Re: ACR 5.6 Canon eos 7D compare to DPP
                                          john cornicello (retired) Level 4

                                          I just used ACR's defaults on this. The only adjustment was to select the profile.

                                          • 18. Re: ACR 5.6 Canon eos 7D compare to DPP
                                            Almanbrother65 Level 1

                                            Here a snapshot of a raw-image. Diffrence between DPP and ACR. All settings are in default.

                                            To get the same exposure in ACR I have to adjust the exposure with ~+0,75. But most of the times it's between +1-+2.

                                            • 19. Re: ACR 5.6 Canon eos 7D compare to DPP
                                              Panoholic Level 2
                                              function(){return A.apply(null,[this].concat($A(arguments)))}

                                              Almanbrother65 wrote:

                                               

                                              Here a snapshot of a raw-image. Diffrence between DPP and ACR. All settings are in default.

                                              To get the same exposure in ACR I have to adjust the exposure with ~+0,75. But most of the times it's between +1-+2.

                                               

                                              I tested with some other Canon cameras and found, that this is not a straightforward issue.

                                               

                                              Example with the 40D: I reset all adjustments, selected the picture style "neutral" in DPP and "camera neutral" in ACR 4.6. I changed the tone curve to "linear" in ACR. I tested on an image with some almost black spots and found, that Blacks in ACR has to be 1 in order to start out from the same level as DPP. Color space=sRGB with both.

                                               

                                              Now the interesting part: dark areas are brighter with ACR; for example DPP's RGB 38-40 requires -0.25 exposure adjustment in ACR. DPP's 116-118 requires +0.85 EV exposure adjustment, and DPP's 224-228 requires +0.65 EV exposure adjustment with ACR.

                                               

                                              In other words, it appears as if the two products applied different tone curves. I would like to know, what is happening.

                                               

                                              Note, that testing with ACR's "Brightness" is not valid, because that affects the bright areas only to small degree.

                                               

                                              Gabor

                                              • 20. Re: ACR 5.6 Canon eos 7D compare to DPP
                                                Almanbrother65 Level 1

                                                Here also a sample, but now from the 1D mark III.

                                                Same settings and same ACR as by the 7D.

                                                Now as you see there is almost no difference in exposure between DPP and ACR only in the green parts at the bottom ACR is a little darker.

                                                • 21. Re: ACR 5.6 Canon eos 7D compare to DPP
                                                  Panoholic Level 2
                                                  function(){return A.apply(null,[this].concat($A(arguments)))}

                                                  Almanbrother65 wrote:

                                                   

                                                  Same settings and same ACR as by the 7D.

                                                  Now as you see there is almost no difference in exposure between DPP and ACR only in the green parts at the bottom ACR is a little darker.


                                                  Hold on!  Brightness = +50 is the same as Exposure = +1.00, except for the highlights. Thus you are comparing very different renderings.

                                                   

                                                  Gabor

                                                  • 22. Re: ACR 5.6 Canon eos 7D compare to DPP
                                                    Almanbrother65 Level 1

                                                    In my image from the 7D, brightness is also set to +50. I guess this is standard in ACR 5.6 because I didn't set it to +50.

                                                    If not and I have to decrease the brightness the difference between ACR and DPP would be a lot bigger, as you can imagine.

                                                    • 23. Re: ACR 5.6 Canon eos 7D compare to DPP
                                                      Panoholic Level 2

                                                      Of course the difference will be much greater without Brightness, but applying it with ACR does not contribute to the explanation of the difference. Some "standardized raw image" would be useful to analyze the actions of the raw converter. I can create such in DNG format, but that does not help in comparison with DPP.

                                                       

                                                      Anyway, I concede that I can't contribute to the solving of this issue.

                                                       

                                                      Gabor

                                                      • 24. Re: ACR 5.6 Canon eos 7D compare to DPP
                                                        Almanbrother65 Level 1

                                                        Thanks anyway for your support!!

                                                         

                                                        Aldert