13 Replies Latest reply: Apr 26, 2012 6:18 AM by Hudechrome RSS

    Question about the New ACR Corrections for Tonal Range

    Hudechrome Community Member

      I find the new set of controls for tonal range in CS7 to be excellent! However, I am curious about what controls what. Black and Shadows work as I would expect but Highlight and Whites do not, at least in terms of traditional photography.

       

      Highlights and Shadows are grouped together as I would expect, Black and White also. But if we are to continue with that progression, White should control the clipping point and Highlights the values a 2 stops or so above middle gray. I would expect Highlights to be similar to Brightness in CS5 except better behaved. It's reversed. Highlights =Recovery in CS5

       

      It's confusing so I am suggesting that White control clipping and Highlight the upper values.

        • 1. Re: Question about the New ACR Corrections for Tonal Range
          Pattie F Employee Hosts

          After setting the overall image brightness with Exposure, use Highlights and Shadows to set the relationship between the midtones, highlights, and shadows.

           

          Whites and Blacks are the highlight & shadow clipping controls.This is useful for adjusting how much of the highlights & shadows are clipped off, while preserving the overall tonal relationships in the image.

           

          Hope that helps.

           

          Pattie

          • 2. Re: Question about the New ACR Corrections for Tonal Range
            Jeff Schewe Community Member

            Pattie Foxhoven wrote:

             

            After setting the overall image brightness with Exposure, use Highlights and Shadows to set the relationship between the midtones, highlights, and shadows.

             

            Not wrong but I would go further...in PV 2012, Contrast has increased in importance. I know many/most user stayed away from adjusting Contrast in earlier versions, but I would suggest right after Exposure you adjust Contrast before going to Highlights and Shadows. If you are working on a low contrast scene, do look at increasing contrast after exposure. If you are working on a high contrast scene, reduct the contrast. The odds are that after contrast you'll see that either the higlights or the shadows will need more attention. The last place to fiddle is Whites and Blacks to fine tune the end points.

            • 3. Re: Question about the New ACR Corrections for Tonal Range
              Noel Carboni Community Member

              Basically, work top to bottom... 

               

              -Noel

              • 4. Re: Question about the New ACR Corrections for Tonal Range
                Hudechrome Community Member

                Thank you Patti for your response.

                 

                I think we are coming to this from different perspectives. Being so close to development of the current upgrade, I appreciate your insights as to how these controls work. I, on the other hand, am coming from long experience as a photographer and printer, exceeding 50 years at this point. So I have some legacy points of view, which is why I posted.

                 

                I spent this evening looking more closely. Here is a summary.

                 

                I messed with an excellent example for looking at this question, and I found something interesting. You can fix an image which already has clipping far easier with Highlights, but you cannot force an image with white values well below clipping into clipping using Highlights. The reverse is true with White. So, to fix a white clip, use Highlights, to force a white clip, use White.

                 

                Blacks and Shadows are different. You can both force and fix a Black clip with Black, but Shadows, while possible, has much less range. So Shadows are kind of vernier on Blacks. This is different than  Whites.

                 

                I was basing my OP on only fixing clipping points, that is, bringing an image out of clipping, but not forcing into clipping.

                 

                So, indeed, what you and Jeff point out is closer to correct than my initial assertions. Yours are based on a broader range controls than possible in analog days. In naming these controls, one winds up with a foot in both the digital side and the old analog side, which gave rise to the names and the meanings.

                 

                So thanks to both you and Jeff for taking this up. It forced me into looking more closely at my conclusions, and while they weren't wrong outright, they were inadequate to the present state of the technology. Sometimes, experience can actually get in the way!

                 

                Lawrence

                • 5. Re: Question about the New ACR Corrections for Tonal Range
                  Hudechrome Community Member

                  Follow-up:

                   

                  I woke early and it occurred to me to see if I might make more sense if I did a couple of experiments in an attempt to do a bit of quantifying. First, I prepared a single gray value 128 and saved it as a tiff, so I could open it in ACR. Surprise! The value in ACR is now 145. So I did a step tablet of but 4 steps and again, the values don't agree.

                   

                  Checking with CS5, it reads 128 in PS, 128 in ACR 6. It is consistent.

                   

                  This discrepancy continues with a simple 4 step step tablet.

                   

                  I can continue by ignoring this discrepancy because ultimately I want to study the changes at different parts of the scale by measuring values of a few steps as adjustments are made. It is informative qualitatively, but the numbers are useless outside ACR.

                  • 6. Re: Question about the New ACR Corrections for Tonal Range
                    L.P.Baker

                    Maybe it's just me, but I cannot stand the new ACR tonal adjustments. Why the change in jargon? I have figured that the Shadow slider is basically a Fill light adjustment, but I miss the Brightness slider! Exposure adjusts highlights first, then upper midtones. Brightness adjusts the overall luminosity of the image starting with the midtones. Blacks should add punch to the darkest areas of the image. Fill light should fill in the lower midtones that are sometimes lost with increased contrast. Maybe I have it all wrong, but since working with the update, I have gotten several jobs back from clients saying that the shadows are lost or contrast is too high. It really has been a frustrating transition! Thanks for all of the tips, though. Maybe I just have to get used to it?

                    • 7. Re: Question about the New ACR Corrections for Tonal Range
                      Noel Carboni Community Member

                      My impression is that it's more "touchy feely" than quantitative.

                       

                      Try not to overthink it, but just move the sliders until the image gets better looking.  Stop when you can't make it better looking.

                       

                      Yes, that seems almost silly, but try that mindset.  It seems to work.

                       

                      -Noel

                      • 8. Re: Question about the New ACR Corrections for Tonal Range
                        Jeff Schewe Community Member

                        L.P.Baker wrote:

                         

                        It really has been a frustrating transition! Thanks for all of the tips, though. Maybe I just have to get used to it?

                         

                        The more you try to apply PV 2010 mentality to PV 2012 image adjustments, the more frustrated you will become. Forget what you THOUGHT you knew and embrace the functionality of the new processing controls. The quicker you become adept & comfortable using the new controls, the quicker you'll be getting better results–because make no mistake about it, PV 2012 is a vast improvement (even if it is difficult to adapt to).

                        • 9. Re: Question about the New ACR Corrections for Tonal Range
                          Hudechrome Community Member

                          Resistance is futile L.P. You will be assimilated. Come over to the dark side . It will be the highlight of your career!

                           

                          Fundamentally, we have a process which is analog, but under digital control. It's not as simple as adjusting  a volume control or a dimmer . Digital and analog have a strained relationship. But then, photography has always had stumbling blocks for the unwary except now those blocks are further complicated by the use of a digital medium for control. The notion of controlling light by turning on and off a whole bunch of switches does not translate well from turning a knob. Yet we are provided a knob or more properly, a slider to do just that.

                           

                          The magic behind it is under the control of the programmer, not you. Notice, for instance, that when you move a slider to the left of -0-, not too much happens. Move it too the right and all hell breaks loose!  And to make matters worse, some sliders are worse than others, seemingly controlling the same part of the scale. But they are not.

                           

                          One tip I would leave is that it is vital that when you move the sliders, you really need to use the Alt-click  (on  PC, I am not sure of Mac) to see when and if you hit the stops. The clipping points show up and become guides for setting limits. In many cases, when you lift your finger from the mouse, you will likely be shocked by what you see, and manipulating the controls then becomes an exercise in restraint. Not all the sliders respond to this; muck around with each to find out which do.

                           

                          So to paraphrase Obi-Wan Kenobi, "May the Programmers be with you"! (Yes I know I've mixed my metaphors!)

                          • 10. Re: Question about the New ACR Corrections for Tonal Range
                            Noel Carboni Community Member

                            Hudechrome wrote:


                            Come over to the dark side.

                             

                            In this case, they really DO have cookies!

                             

                            I've noticed, however, that PV2012 is more "touchy feely", and those who think more analytically (as I think you do, Lawrence) seem to have more trouble making the adjustment.

                             

                            Let go.  Use the force.  Turn off your targeting computer.  Just move stuff around until the image looks better!

                             

                            One thing, though, and your comment about "lifting your finger off the mouse" reminded me...  Your system needs to be up to displaying the image changes in real time for "touchy feely" to work well.  Are you not seeing the screen update WHILE you're moving the sliders?  I am.

                             

                            -Noel

                            • 11. Re: Question about the New ACR Corrections for Tonal Range
                              b2martin_a Community Member

                              I don't understand you comment about the gray values relative to ACR7 vs ACR6. 

                               

                              I selected 50 RAW (NEF) files and converted these to JPG images using default values for both ACR6 and ACR7 (No adjustments to any images) .  I renamed the images so they would appear next to each other in a file.  I then ran a slide show of the images which first shows the ACR6 conversion and then switches to the ACR7 conversion of the same image.  I could not detect any change when the viewer switched between the ACR6 to the ACR7 conversion of the same image.  If there is a difference like you measured with your gray test I should see a difference in the two conversions, if I understand your test. 

                              • 12. Re: Question about the New ACR Corrections for Tonal Range
                                Hudechrome Community Member

                                I see the real time updates as well. I see that even with Alt. is held. For Shadows, the screen goes white and the first appearance of any tone or color indicates clipping has occurred. The opposite is true for highlights. Exposure gives a view of Highlight clipping only.

                                 

                                So fart as touchy-feely is concerned, I ultimately default to that once I have thoroughly understood the underlying operations.  My goal is to get there, just as my goal when playing the piano becomes touch and feel, but doesn't start there as a beginner. In either case, for me anyway, it isn't either/or. It's a continuum.

                                • 13. Re: Question about the New ACR Corrections for Tonal Range
                                  Hudechrome Community Member

                                  I am referring (in Post#5) to the values that show up with a single gray set to some number like 128. But it also shows up with a real image. I noticed it first in cloud values. It may be local and not universal, which is why I posted it. Your the first to respond, and I wondered why it hasn't been acknowledged or refuted by others until now. That a single gray value in ACR would measure different than in Photoshop is disconcerting. It isn't true in CS5.