10 Replies Latest reply on Jun 1, 2015 8:00 AM by trshaner

    Auto whites and blacks

    Alp Er Tunga Level 1

      We know that auto "whites" and "blacks" (shift + double click on these sliders) are responsive to changes made to other sliders ... or cropping the image etc.

      But, after applying general auto tone adjustments by clicking on "Auto" button ... why shift + double click on "whites" and "blacks" sliders give different results without making any change on the adjustments set by "Auto" button?

        • 1. Re: Auto whites and blacks
          thedigitaldog MVP & Adobe Community Professional

          I'm not sure, but I've found that the shift double click differs produces differing results upon the image depending on the order you apply them (try top to bottom, reset, then bottom to top). I assume the auto is somewhat image state dependent which might explain what you're asking about and why the order of application produces different results.

          We'd need an Adobe engineer or staff to confirm of course.

          • 2. Re: Auto whites and blacks
            99jon Adobe Community Professional & MVP

            Would be useful to know what is behind the algorithm. Maybe white and black points should be set first before using the sliders for highlights, shadows and exposure?

             

            A good trick is to hold down the shift key and double click on the word “black” or “white” which is slightly easier than clicking on the slider pointer.

            • 3. Re: Auto whites and blacks
              Alp Er Tunga Level 1

              Let me explain my point with an example ...

               

              The image below shows the clipping points set by shift + double click on "whites" and "blacks" without any other adjustment made before:

               

              1.jpg

               

              If we first set any other control, let's say exposure, shown below ... then now clipping points set by shift + double click differ as expected ... because auto "whites" and "blacks" are responsive to other changes made before. They are also responsive to cropping ... that is, if you crop your image, clipping points differ set by shift + double click.

               

              2.jpg

               

              It is ok so far, there is no strange behaviour for me ... clipping points are changing, because we are changing an another slider and the clipping points are responding to these changes.

               

              But, here is my point, after using general "Auto" button, clipping points are also changing withouth making any change on adjustments set by "Auto" button. So, as you see, when there is no change on any adjustment, shift + double click gives different results.

              3.jpg4.jpg

               

              The first image above shows the state after the general "Auto" button clicked .... second image shows the result after shift + double clicking on "whites" and "blacks".

              • 4. Re: Auto whites and blacks
                thedigitaldog MVP & Adobe Community Professional

                99jon wrote:

                Would be useful to know what is behind the algorithm. Maybe white and black points should be set first before using the sliders for highlights, shadows and exposure?

                I think the order is the key here. It's as if the tools are adaptive to the image content at the state you click on the slider.

                • 5. Re: Auto whites and blacks
                  Victoria Bampton LR Queen Adobe Community Professional & MVP

                  Andrew Rodney wrote:

                  I think the order is the key here. It's as if the tools are adaptive to the image content at the state you click on the slider.

                   

                  That's correct. The shift double click is based on any existing image adjustments and crop boundaries (including slider positions created by the global auto adjustment), unlike the basic auto settings. The change was introduced in 5.3, if I remember correctly.

                  • 6. Re: Auto whites and blacks
                    Alp Er Tunga Level 1

                    thedigitaldog wrote:

                    I think the order is the key here. It's as if the tools are adaptive to the image content at the state you click on the slider.

                     

                     

                    Does this mean that ... the general "auto" button sets the clipping points before making some other changes on other tone sliders.

                    If so ... should the clipping points always be revisited by shift + double clickling on "whites" and "blacks" after using general tone auto adjustments button ... for correcting the clipping points for the latest state of the image?

                    • 7. Re: Auto whites and blacks
                      thedigitaldog MVP & Adobe Community Professional

                      Alper Tonga wrote:

                      Does this mean that ... the general "auto" button sets the clipping points before making some other changes on other tone sliders.

                      Again, it depends on the order of any previous edits if any. I can count on one hand the number of times I've used Auto so I'm probably not the person to be asking

                      • 8. Re: Auto whites and blacks
                        trshaner Adobe Community Professional & MVP

                        Crop settings have no effect on Auto Tone settings in LR CC on Windows 7. Also the Shift-Click "order of application" makes no difference for Exposure, Contrast, Highlights, and Shadows controls. These Auto Tone controls are also not affected by the Whites and Blacks settings, but the Whites and Blacks settings are by the other Tone control settings.

                         

                        From my experience the one-button Auto Tone isn't bad, but the resultant Exposure setting is almost always wrong. The majority of images should be pretty close with the just readjustment of the Exposure setting. If not you're better off resetting the Tone controls (double-click 'Tone') and then manually readjusting starting with the Exposure control and working downwards.

                        • 9. Re: Auto whites and blacks
                          thedigitaldog MVP & Adobe Community Professional

                          trshaner wrote:

                          Also the Shift-Click "order of application" makes no difference for Exposure, Contrast, Highlights, and Shadows controls. These Auto Tone controls are also not affected by the Whites and Blacks settings, but the Whites and Blacks settings are by the other Tone control settings.

                          Indeed, thanks for pointing that out. It appears the order does affect Blacks. I get a vastly different result or value if I use it first versus using it last (-11 vs. -26). And Auto produces different results than clicking on each in order (top to bottom). Whites give me a different value moving in order top to bottom than just using Auto alone (-51 vs. +15 which is significant).

                          • 10. Re: Auto whites and blacks
                            trshaner Adobe Community Professional & MVP

                            Whites and Blacks Shift-Click results are affected by all of the other Tone control settings, which makes sense. The anomaly as the OP points out is that the Whites and Blacks settings change when using Shift-Click after Auto Tone is applied.


                            I did a test on images with different exposure and dynamic range. Those that look good with Auto Tone applied had minimal change when using Shift-Click on Whites and Blacks after Auto Tone. The ones that looked over (or under) exposed showed larger changes in the Whites and Blacks Shift-Click results. In most cases readjusting just the Exposure control on those images also provides very usable Whites and Blacks clipping points without changing their settings.