10 Replies Latest reply on Oct 27, 2015 3:43 PM by trshaner

    Correct Use of Lightroom's Clipping Indicators

    1ndivisible Level 1

      The clipping indicators in Lightroom show when a channel or all channels are clipping in either the shadows or the highlights, but I've seen them used in two ways:

      1. Use them as an indicator of when you have a pure white / black so that for a full tonal range both shadow and highlight clipping indicators will be showing (although perhaps only a tiny number of pixels will actually be clipped.
      2. Use them as an indicator of when you have gone too far, so when a clipping indicator shows, the user backs off slightly, so for a full tonal range the white and black points will be just short of triggering the clipping indicators.

      So which is correct? Do they indicate a value has been pushed beyond maximum (or minimum) or that a value is at maximum or minimum?

        • 1. Re: Correct Use of Lightroom's Clipping Indicators
          dj_paige Level 9

          Either is correct.

           

          Depends on what you are doing.

           

          By the way, sometimes, I will use the clipping indicators only as an indicator, and edit such that there is a lot of clipping because I like the way the photo looks at that point.

          • 2. Re: Correct Use of Lightroom's Clipping Indicators
            1ndivisible Level 1

            I don't see how either can be correct. For example either the highlight clipping indicates that pixel has reached its maximum luminance value or it indicates that it has gone beyond it. It can't do both as they are two discrete states.

            • 3. Re: Correct Use of Lightroom's Clipping Indicators
              dj_paige Level 9

              There is no global "right" method to edit your photos. Some people use one method, other people use another method. You can throw these rules out the window if you are happy with the end result.

               

              If the edit looks good to you, then you have a success. If the edit doesn't look good to you, then you don't have a success.

              • 4. Re: Correct Use of Lightroom's Clipping Indicators
                trshaner Adobe Community Professional & MVP

                1ndivisible wrote:

                 

                I don't see how either can be correct. For example either the highlight clipping indicates that pixel has reached its maximum luminance value or it indicates that it has gone beyond it. It can't do both as they are two discrete states.

                The Histogram clipping indicators change color to indicate, which channels have reached maximum. The RED Highlight and BLUE Shadow clipping mask (i.e. when you click on Histogram clipping indicator) indicates one or more channels is at maximum. It can't tell you what colors are actually clipped. You can also hold down the Shift key and double click on the Whites or Blacks sliders to set the clipping points (~0.1%). IMHO none of these indicators are very useful for adjusting real-world "picture" image files. Some pictures should have aggressive clipping (bright sunlight with deep shadows) and some none (overcast, or fog lighting). As mentioned, "If the edit looks good to you, then you have a success." The clipping indicators help set a starting point, but only you can determine when to increase or decrease the clipping levels.

                 

                A better way to set highlight and shadow clipping is to hold done the ALT key when adjusting the Whites and Blacks sliders. Notice I didn't include Exposure, which should be used to set the midtone brightness with PV2012 Tone controls. More suggestions here:

                 

                Re: Editing question

                • 5. Re: Correct Use of Lightroom's Clipping Indicators
                  1ndivisible Level 1

                  I asked the same question on Stack Exchange Photography, and here is the clearest answer from Abdul N Quraishi:

                  When looking to set a maximum black or white point, both scenarios you mention can be regarded as correct or incorrect as they both provide you with an indication only.

                  If developing to export in jpeg for displaying on monitor only, then the triangle in the histogram turning to white will not have any noticeable affect on your image.

                  However, if you were developing to print, then any pixel that is blown out, will not be printed. The printer cannot print white and this will be immediately noticeable on paper.

                  Going back to the histogram, the clipping happens in stages, and if you look at the indicator, before turning to white, it can turn, Pink, Yellow, Cyan etc indicating which channel clips first.

                  with certain types of images, EG, fine art prints, textiles or jewellery, it is imperative to understand that this process of the first channel clipping can start when the RGB pixel value reaches 242/245 but the triangle will not turn white till 255, at which point, there is a loss of detail.

                  The way to correctly judge the pixel values of the image is to turn on Soft Proofing in LR. this will then allow you to hover over your image and correctly see the separate RGB values under the Histogram chart and as a result, help you manage your black and white points more effectively to ensure there is no clipping.

                  Therefore, the answer to your question which is correct?

                  Scenario 1 can be used when developing for viewing on monitor only

                  Scenario 2 is better suited when developing for print.

                  And finally, the answer to your question, do they mean at or over, the answer is over. If you wait for the triangle to turn white, then you have already lost some detail.

                  • 6. Re: Correct Use of Lightroom's Clipping Indicators
                    trshaner Adobe Community Professional & MVP

                    1ndivisible wrote:

                     

                    I asked the same question on Stack Exchange Photography, and here is the clearest answer from Abdul N Quraishi:

                    If developing to export in jpeg for displaying on monitor only, then the triangle in the histogram turning to white will not have any noticeable affect on your image.

                     

                    For screen viewing and printing of normal and high contrast images there should be areas of the image that are fully clipped in both the highlights and shadows. Lacking that you are not utilizing the full dynamic range of the medium (Display Contrast Ratio and Printer Dmax). The only exception is when working with low contrast images, such scenes with heavy fog or overcast sky. In order to reproduce the scene as it appeared there should be virtually no shadow or highlight clipping. For these lighting conditions setting the White and Black points to clipping will produce an image that looks nothing like the original scene. As already mentioned, you need to determine the desired rendering with your eyes when making the final adjustments.

                     

                    1ndivisible wrote:

                     

                    I asked the same question on Stack Exchange Photography, and here is the clearest answer from Abdul N Quraishi:

                    if you were developing to print, then any pixel that is blown out, will not be printed. The printer cannot print white and this will be immediately noticeable on paper.

                    Total confusion here! This is in fact exactly how printers reproduce White. You can see this using the target paper profile in LR Soft Proof mode by checking 'Simulate Paper & Ink.'

                     

                    1ndivisible wrote:

                     

                    I asked the same question on Stack Exchange Photography, and here is the clearest answer from Abdul N Quraishi:

                    with certain types of images, EG, fine art prints, textiles or jewellery, it is imperative to understand that this process of the first channel clipping can start when the RGB pixel value reaches 242/245 but the triangle will not turn white till 255, at which point, there is a loss of detail.

                    When processing raw image files inside LR it is impossible to determine if the actual raw data is clipped in any areas of the image. If you use the Highlight slider to recover blown-out areas it is possible to extinguish the clipping indicator leading you to believe all is well. In fact those RGB pixels may be fully blown in the raw data and better off being left that way. Yes, you can recover areas that are clipped in only one or two channels, but this can produce inaccurate colors that look unnatural (i.e. gradients in sky areas).

                     

                    So all of this double-talk about Highlights that are clipped, partially clipped, only clipped in one channel, etc. is an exercise in futility! Lightroom currently has no way of indicating raw data clipping in the preview image. Here's a good example using Raw Digger. The solid Red areas are 100% clipped (maximum value) in all four raw data channels (RGGB). But in the adjusted LR image it appears that only the central area of the Sun is clipped, which obviously isn't the case. All matter of "tweaking" the LR Tone controls cannot bring back blown raw data pixels!

                     

                    In the final analysis the eyes have it right.

                    Highlight Clipping Inidcator Example.jpg

                    • 7. Re: Correct Use of Lightroom's Clipping Indicators
                      1ndivisible Level 1

                      Thanks for your lengthy and detailed reply. You are right that there is much confusion here.

                       

                      So would it be fair to say that the clipping that is shown in Lightroom (by indicators or by holding down alt when using certain sliders) indicates output clipping of one or all channels as opposed indicating that the RAW data itself is clipped?


                      I think I understood this already (your example of the sun is perfect), but you have made it explicit in my mind.


                      In actuality, my question was never about whether an image should have a full range (from pure white to pure black), as this is a creative decision or at least a decision based on the subject; your example of mist being the canonical exception.  All I actually wanted to know was at the most basic level, whether the clipping indicators were triggered at the moment a channel was clipped, or on the brink of a value being clipped. In much the same way as a car's parking sensor would beep constantly not at the moment of impact, but the moment just before impact (in fact probably it would leave a gap by design). I was interested in Lighroom's designers intended the clipping indicators to show that you were about to hit the wall or had already hit it. That is all. Turns out no--one is sure of which of those two is the correct answer.

                      • 8. Re: Correct Use of Lightroom's Clipping Indicators
                        trshaner Adobe Community Professional & MVP

                        1ndivisible wrote:

                        So would it be fair to say that the clipping that is shown in Lightroom (by indicators or by holding down alt when using certain sliders) indicates output clipping of one or all channels as opposed indicating that the RAW data itself is clipped?

                        That is correct. Once the camera profile is applied in LR the raw date has been modified. It is impossible to determine the actual raw data values inside LR....at least currently.

                         

                        1ndivisible wrote:


                        I think I understood this already (your example of the sun is perfect), but you have made it explicit in my mind.

                        It's sometimes hard to see things out of the "picture context." Being an engineer helps (45 years in system design).

                         

                        1ndivisible wrote:


                        All I actually wanted to know was at the most basic level, whether the clipping indicators were triggered at the moment a channel was clipped, or on the brink of a value being clipped.

                        Well you can test this for yourself. Here's raw image uniWB test shot with no raw clipping pushed to show clipping inside LR. The RGGB levels of the UniWB raw file are all equal, but after the camera profile is applied the RGB values inside LR are at different levels (pink color). The first screenshot shows the levels inside the clipped area and below outside the clipped area. The actual "trigger level" appears to be at 99.8% for any one channel, which is a 254.49 value for 8-bit data (255 max.). Edit in PS shows 255 in the clipped area and 254 at the border of the clipped area.

                         

                        So it looks like to me the Adobe Engineers want the Highlight indicator to trigger when any one channel hits the wall.

                        Highlight Clipping Indicator Test.jpg

                        • 9. Re: Correct Use of Lightroom's Clipping Indicators
                          1ndivisible Level 1

                          Amazing answer. Thanks very much. Would you like to add this last part as an answer here: exposure - Do the clipping indicators in Lightroom show that the value is at the maximum, or beyond? - Photography Stack…

                           

                          Or would you mind if I added it and linked back to here?

                          • 10. Re: Correct Use of Lightroom's Clipping Indicators
                            trshaner Adobe Community Professional & MVP

                            1ndivisible wrote:

                            Or would you mind if I added it and linked back to here?

                            That is fine with me.