20 Replies Latest reply on Nov 17, 2010 2:25 PM by Hudechrome

    Ctrl/Cmd-U Actions

    Hudechrome Level 2

      I just today looked into this shortcut. It has advantages, at least for a look-see, but it also has a problem.

       

      When choosing multiple images to open in ACR, "Select All and Synchronize", the process does not synchronize when selecting the shortcut. Each image is corrected on it's own, and all the slider values from Exposure to Contrast go blank. Checking the settings of each image separately shows that they are not equally set, as now all the slider values are visible.

       

      There is a workaround for this by simply  picking the frame best suited first,  hitting "Select All", then "Synchronize" again, and now all the values are the same, and the info in the sliders are shown.

       

      I suspect this is a bug, because I can tell you that if the set of images to be corrected are part of a stitch, it will be strange. You may as well have the camera on auto when running the set in the field, then not even use ACR before the stitch.

       

      Now, when the individual images are not intended for stitch, as perhaps in a series of wedding photos, that individual setting for each frame might be of value, but not being informed of the auto function applying different settings when in Synchronize is not any sort of advantage from my POV.

        • 1. Re: Ctrl/Cmd-U Actions
          Jeff Schewe Level 5

          Hudechrome wrote:

           

          I suspect this is a bug, because I can tell you that if the set of images to be corrected are part of a stitch, it will be strange.

           

          No, it's as designed and for good reason...when you have multiple images open in ACR and you apply an Auto correction, each image will get it's own specialized auto correction...that's the whole purpose of "Auto". And, since each image then may have different settings in the various parameters, ACR intentionally shows no adjustment (blank) when multiple images are selected...this is actually a useful function since you then see which settings are different between the images.

           

          If you don't want to use the Auto function across images, you don't have to. But the current behavior and logic are absolutely correct and I'm pretty darn sure there won't be any changes to this feature.

          • 2. Re: Ctrl/Cmd-U Actions
            Hudechrome Level 2

            If it wasn't for the blank info, I wouldn't have noticed the images were not synched.

             

            I have no argument with the nature of individual corrections in Auto on a series of images enabled by Select All. I have serious reservations in the fact that when Sync is selected they are not synched across all the parameters checked in the check box. That is the problem, and since you say it is deliberate, it can't be called a bug, but I will call it an oversight in not informing the user of this property.

             

            Having multiple images open isn't the same as having multiple images open, selected and synched.

            • 3. Re: Ctrl/Cmd-U Actions
              Jeff Schewe Level 5

              Hudechrome wrote:

               

              I have no argument with the nature of individual corrections in Auto on a series of images enabled by Select All. I have serious reservations in the fact that when Sync is selected they are not synched across all the parameters checked in the check box. That is the problem, and since you say it is deliberate, it can't be called a bug, but I will call it an oversight in not informing the user of this property.

               

              The Auto command is not an absolute setting...it is image dependent. Therefore you can't Sync the Auto command. If you do an Auto and then do a Sync, the Sync does override the Auto across selected images...if this is not what you are seeing then I don't know what to tell you. Same deal with Sync and then an Auto...the Auto will override the previous Sync. As far as I can tell, everything works as designed (and expected).

               

              Since Auto does produce different results based on the image, what would you expect to see if multiple images with different results are selected? The only settings that will show are those settings which are exactly the same across all selected images. The fact that some are blank is an indicator that the settings are not the same on all selected images. That is a feature not a bug.

              • 4. Re: Ctrl/Cmd-U Actions
                Hudechrome Level 2

                I pulled back on calling it a bug, so we can drop that part.

                 

                I called it an oversight as the process is non-intuitive, based on the performance expected from doing manual correction.

                 

                My way of setting it up is that IF Select All And Synch are selected, anything done to the highlighted image applies to all. That is consistent behavior, not the convoluted "Well if you do Auto, it doesn't apply to Sync because it overrides". Why? It's nonsense to do it that way. Inconsistent behavior is a major cause of the loss of gumption, and gumption loss is good work lost is cause to turn away from apps that indulge in it.

                 

                Any there are plenty to go around.

                 

                My opinion anyway, but then, I'm not, nor ever will be, a guru.

                 

                Oh, and yes, I did explain my work around. I do it that way because using Auto is good, investigative step. Now I know if I stay with auto, I have to invoke Synch again. Otherwise, if I wait till later to select Synch and decide against Auto, I have to remember to invoke Synch, which will now be a departure from my workflow for multiple images.

                 

                My request is that the override feature be in the hands of the user, not the software writers, and be prominent. Some of them (not all, perhaps not even the majority) don't have a clue about workflow.

                • 5. Re: Ctrl/Cmd-U Actions
                  Hudechrome Level 2

                  Since the weather is so bad and a problem with Win7 yielded to a solution faster than expected, I decided to amuse myself by messing more with all the sliders in ACR.

                   

                  For my defaults, all the sliders are set at the basic defaults existing when I first opened ACR, except that I set the Clarity to 10. Camera Calibration is set at camera Standard, all the rest of the control panels are at neutral or 0.

                   

                  So I ran some images using Auto or Ctrl-U as a starting point. Without exception, the Brightness and Contrast were the most commonly moved sliders. Seems I simply cannot get it right in the camera. (What a dufus! )

                   

                  One particular image grabbed my attention as virtually all the sliders had moved. I hated the result, so I proceeded from that point to readjust to my taste. A few minutes later, I was reasonably satisfied. All the sliders were at some point other than default and other than Auto. One would expect that. So I unchecked Preview. Whut? No change! Try again.Yep the tiniest of change was noted. So watching the Histogram, I set the system back to Camera RAW defaults, and sure enough the barest shift in the histogram was noticed, mostly a shape change in the blue channel, and the image looks the same as the adjusted image.

                   

                  The point I am trying to make is that the sliders, when set by eye for best results, were way off the defaults yet the image and histogram matched. So, why all the sliders? I recall that a person asked why as well since the Exposure slider and the Brightness apparently do the same thing. The current writer for the ACR manual said they actually were different yet it seems that I can neutralize the Exposure slider with Brightness, and visa versa.

                   

                  FAPP, other than test, I never touch the Brightness slider, sometimes the contrast slider. I can always get very close with the rest available. The Black slider is offensive past about 9 or so as the image saturates to the extent that I have to resort to the Sat and Vibrance controls to balance it out. If Luminosity was a choice for blending in ACR, I would definitely use it to kill off the excessive color shift just to get a good black. So I reserve this for PS where I do have this control.

                   

                  Anyway, this is one person's perspective on ACR, which is a wonderful app so far as I am concerned.

                   

                  If I had my druthers, here are a few changes to be made:

                   

                  Introduce Blending Mode

                   

                  Provide History (important when using the Adjustment Brush)

                   

                  Be consistent with how functions operate, and allow the departures from expected to be the exception, not the rule (Auto in multiple image correction)

                   

                  Fix the Adjustment Brush so that the size change key works all the time (Same for several brush modes in PS, like The Burn, Dodge and Sponge tool)

                  Ok I can hear it now. "That's not a bug, it's a feature!"

                  • 6. Re: Ctrl/Cmd-U Actions
                    Jeff Schewe Level 5

                    Hudechrome wrote:

                     

                    I recall that a person asked why as well since the Exposure slider and the Brightness apparently do the same thing. The current writer for the ACR manual said they actually were different yet it seems that I can neutralize the Exposure slider with Brightness, and visa versa.

                     

                    No, actually you can't...similar but not the same.

                     

                    The Exposure slider is the white clip adjustment. If you increase Exposure you can actually introduce white clipping. The Brightness slider adjusts the mid point (lighter or darker) based on the Exposure and Blacks setting. But Brightness can NOT clip–try it...once you understand the relationship between Exposure (white clipping) Blacks (shadow clipping) and Brightness (the midpoint settings based on the settings of Exposure and Blacks) you can easily understand their relationships and use them. If you think Exposure and Brightness do the same thing, you don't understand how to use the adjustments...

                    • 7. Re: Ctrl/Cmd-U Actions
                      Hudechrome Level 2

                      Thanks, Jeff, I'll take a closer look.

                       

                      But you cannot deny that they do highly interact, to the extent I found, anyway. The image had no white point so perhaps that's why I could do what I did.

                       

                      What the Brightness slider seems to do from your description is similar to adjusting curves in PS by changing the center point. I know that does not introduce clipping either.

                       

                      Now we come to the ACR curves. I presume that similar effects accrue this adjustment as well, that is increasing Brightness w/o clipping.

                       

                      I'll play around some more. Because I did not fully understand the presence of the Brightness vs Exposure, I tended to leave it alone. I seldom set any sort of clipping in ACR, preferring to do that in PS to establish black and white points prior to printing. This feels congruent to printing in the darkroom, that is establishing paper white and max black as a necessary routine in making the fine print. But in silver printing, contrast and exposure establish this range with respect to the density range in the neg itself. No Brightness slider!

                       

                      Of course there are now many photographers today that have little or no experience with fine printing a la darkroom days and they do not have the imitations programmed by years of burnishing one's technique with chemistry and light.

                      • 8. Re: Ctrl/Cmd-U Actions
                        Hudechrome Level 2

                        I did more tests and these are my findings.

                         

                        My subject is a photo of a thunderhead underexposed by about 2 stops. There are no whites at all; the max white is about 103 on the histogram, ACR at default. I first used Brightness to try and max out the white values, I was only able to move them to ~200. Setting the Contrast slider to max raised it to ~225.

                         

                        Reset to normal. Move the Exposure slider. Clipping of highlights commences with the slider set to 3.15, blue clipped, and is complete at 3.35 all channels clipped.

                         

                        Next, set the Exposure noticeably below any clipping Dropping from 3.15 to 3.0 accomplishes this. Now, I move the Brightness to see if I can clip. Clipping starts at 106 (Blue channel) at at 140, clipping is complete .

                         

                        So, where does Exposure need to be set so that no clipping occurs with the Brightness set at max? With this sample, it is 2.95 with RGB showing 254, 255, 255.

                         

                        That no clipping ever occurs using the Brightness slider is disproved, although the margins are very close.

                         

                        Another interesting test of the Brightness slider is:

                         

                        Can clipping as instituted by the exposure slider be compensated by dropping Brightness? The answer is No, once clipping has commenced, in any channel using Exposure, it remains clipped.This is visually obvious

                         

                        There is the temptation to consider this an anomaly; it's only one sample. Unfortunately, (or fortunately, depending on the persons pov!) only one instance of a theory's failure is necessary to prove the theory false.

                         

                        I don't know if the algorithm governing the Brightness behavior can be tweaked, or given the margins here, is actually necessary. But if the goal is that  clipping never occurs using Brightness is important, then I believe it needs attention.

                         

                        Note: This experiment carried out to the best of my abilities with the tools available. There may be extenuating circumstances beyond my awareness that alters the outcome, so I am interested in any feedback addressing this issue.

                         

                        Lawrence

                        • 9. Re: Ctrl/Cmd-U Actions
                          Jeff Schewe Level 5

                          Hudechrome wrote:

                           

                          That no clipping ever occurs using the Brightness slider is disproved, although the margins are very close.

                           

                          Uh no...you actually proved that Brightness DOESN'T clip..."I first used Brightness to try and max out the white values, I was only able to move them to ~200. Setting the Contrast slider to max raised it to ~225."

                           

                          Using Brightness WITH an Exposure adjustment CAN clip...but it's the Exposure that is causing the clip not the Brightness.

                           

                          I never said that Brightness when used with other adjustments won't clip...I said Brightness won't clip (which you proved).

                           

                          So, now that you are learning Exposure, Blacks and Brightness you might want to learn Curves next–which I tend to use instead of brightness and contrast because it offers more control.

                          • 10. Re: Ctrl/Cmd-U Actions
                            Hudechrome Level 2

                            Please read the entire test.

                             

                            Recall I started with an image well under exposed with which to begin.

                             

                            "My subject is a photo of a thunderhead underexposed by about 2 stops"

                             

                             

                            What I started from is the default point, and it didn't clip using Brightness. Then, set the exposure to just under clipping (or have an image whose values lie just below clipping) and clipping will occur with Brightness.

                            • 11. Re: Ctrl/Cmd-U Actions
                              Jeff Schewe Level 5

                              It's clipping because of the Exposure setting not because of the Brightness setting. Exposure clips, Brightness doesn't. Get it? Brightness on top of Exposure can cause clipping because of the Exposure setting...

                              • 12. Re: Ctrl/Cmd-U Actions
                                Hudechrome Level 2

                                No, the exposure is deliberately set just below the clip point and then the Brightness moves it to the clip point. I did it two ways and it is valid. But you are right on your assertion that Brightness on top of Exposure causes clipping. That's what I am saying. Brightness at 50, no clip. Brightness at 140, clip. Exposure alone had yet to hit the clip point.

                                 

                                A would say it's relatively minor, because under most circumstances, using Brightness does not introduce clipping. But in no way can it be said that using Brightness will never cause clipping.

                                 

                                I tried it on another image after reading your first rebuttal, an image including glare on water. It looks nearly clipped in default and moving the brightness did not clip it. But adding just a bit of Exposure, but not yet clipped as indicated by the triangle AND the RGB numbers, I did get it to clip with Brightness.

                                 

                                So, in general, using Brightness in place of Exposure provides an element of safety with respect to clipping, (you have to work at it to get it to clip) but it isn't fail safe. In the majority of circumstances, where the white point is substantially below clipping, either Exposure or Brightness will accomplish similar ends. And now, I'll incorporate what I have learned into my workflow, keeping Exposure below the clip point and doing any increases with Brightness.

                                 

                                I'll still need to monitor clipping, in any case.

                                • 13. Re: Ctrl/Cmd-U Actions
                                  Jeff Schewe Level 5

                                  Hudechrome wrote:

                                   

                                  No, the exposure is deliberately set just below the clip point and then the Brightness moves it to the clip point.

                                   

                                   

                                  No...the Exposure adjustment is responsible for moving the end point to the extent where that Exposure adjustment can allow Brightness to be used to push the grouping of highlight data to clip.

                                   

                                  You really don't quite grok the differences yet. Once you do, you'll get over the hump. Then you can quit using Brightness and Contrast and start using Curves (either parametric or point curves) to further modify and control the final tone curve. Ultimately, Curves plus Exposure & Blacks is where you gain finesse control over the rendering of tones...then add in local Adjustment Brush settings to finalize the tone curves...

                                   

                                  Baby steps...

                                  • 14. Re: Ctrl/Cmd-U Actions
                                    Hudechrome Level 2

                                    I get it very well. I did basically agree with you. You don't get I get it.

                                     

                                    I use curves all the time, since PS 5, in fact. Curves are my lifeblood in hardware and in photography, analog or digital.

                                     

                                    I stand by my numbers. If you are close to clipping but not yet clipped, Brightness can push you over the edge. It matters not how you get there.

                                     

                                    You actually agree with me as you say:
                                    ... where that Exposure adjustment can allow Brightness to be used to push the grouping of highlight data to clip.

                                     

                                    Anyway, you told me to try it and I did. These are my results.

                                    • 15. Re: Ctrl/Cmd-U Actions
                                      Jeff Schewe Level 5

                                      Hudechrome wrote:

                                       

                                      If you are close to clipping but not yet clipped, Brightness can push you over the edge. It matters not how you get there.

                                       

                                      Yes, actually it does...in your example it was the Exposure component of the two adjustments that caused the clipping even though the amount of Exposure adjustment by itself wasn't enough to cause the clipping. Since Brightness is designed to move the mid-point of the result of the white clip and black clip points, it's adjustments moves the middle. Clearly all the adjustments in Camera Raw interact and are interdependent. But taken by itself, Brightness is designed NOT to clip while clipping is what the Exposure control is designed to do. Yes, on the surface both controls will "lighten" an image...but in different ways (otherwise there would be no need for both).

                                      • 16. Re: Ctrl/Cmd-U Actions
                                        Hudechrome Level 2

                                        Then we are generally in agreement. Your findings basically agree with mine

                                        except for how I got there. Allowing for interdependence takes care of the

                                        details.

                                         

                                        Thanks, Jeff.

                                        • 17. Re: Ctrl/Cmd-U Actions
                                          hillrg Level 2

                                          Hudechrome

                                           

                                          It is nice to see you working toward mastery of ACR.  There are several books out there that make all this very clear, so you might  want to study up a little before contesting results with Jeff.  As you may know, Jeff is an authority on ACR and photoshop.  I doubt there is anyone, with the possible exception of the ACR software engineers, more knowlegible.  All I'm saying is, instead of arguing with Jeff, take his words to the bank.  If what Jeff says is contrary to your present understanding, then your first assumption should be you are wrong.

                                           

                                          Regards

                                          Rory

                                          • 18. Re: Ctrl/Cmd-U Actions
                                            Hudechrome Level 2

                                            Bad assumption, Rory. you might be right after all, and if their answer is unsatisfactory it is only proper to pursue it. Answering a assertion by saying you don't understand the tool is a bogus answer, or at least, as horribly weak answer.

                                             

                                            Science and engineering is advanced by skepticism. Giving that up is giving in to authority, instead of standing for what you know. If the assertion is wrong, there should be definitive rebuttals which stand on their merits, not the individual's reputation.

                                             

                                            Computers and their programs, even electronics itself, has little that is unassailable. One of the best books in my library is called "The Art of Electronics". (emphasis mine).

                                             

                                            In gray areas I am wrong more than I am right, but I generally get to the bottom, closer to the truth at least, if not square on and I do so by being able to replicate the answers I am given. If not, then there is more work to do.

                                             

                                            Sometimes, "They" are actually wrong! Saints perserve us!

                                            • 19. Re: Ctrl/Cmd-U Actions
                                              hillrg Level 2

                                              I agree you need to test everything, but you also need to do your homework.  Part of that is figuring out who knows what.  In any case, keep asking questions - the good folks here donate a lot of their expert time helping those on the steep part of the learning curve.

                                               

                                              Cheers

                                              Rory

                                              • 20. Re: Ctrl/Cmd-U Actions
                                                Hudechrome Level 2

                                                I've been here since 2002.