Highlight/Whites and Shadows/Blacks sliders in ACR

[John Chardine]

In a post I made today I mentioned these sliders. Then I had a closer look at them and on the surface the Highlight/Whites and Shadows/Blacks sliders appear to do very similar things to a RAW image. Can anyone clarify the similarities and differences in their effects.

Thanks.

[DickLudwig]

All the sliders work in the same manner i.e. move the slider to the right and you increase/brighten the effect, move the slider to the left you decrease/darken the effect. The individual sliders are designed so that an individual tonal range is affected. So Whites only affect the very brightest tones, Highlights only affect tones in the mid bright area, Shadows affect only tones in the mid dark areas and Blacks only affect the darkest tones. To see how the sliders work bring up an image that has a histogram that is spread evenly across the histogram. A perfect example of an ideal image to work on is the Monitor Calibration Strip at the bottom of the page. Once you've brought this image into ACR/LR move the 4 tonal sliders and see what part of the histogram is affected by each slider. Move one slider at a time and move it right to see its effect and then to the left and see its effect. Now center that slider before moving the next slider so you are only moving/changing one of the four tonal areas at a time. Do this a number of times until you fully understand what tonal areas are affected by each slider. This is an extremely powerful tool that can take an image and really make it "sing" by just adjusting these 4 sliders.

[John Chardine]

Thanks Dick. I use the sliders often and find them very useful. So the main difference is part of the histogram where the main effect is- Whites having more of an effect farther to the right than Highlights and the same for Blacks/Shadows only in reverse.

[DickLudwig]

Thanks Dick. I use the sliders often and find them very useful. So the main difference is part of the histogram where the main effect is- Whites having more of an effect farther to the right than Highlights and the same for Blacks/Shadows only in reverse.

You got it.