Adjusting image tones directly using the histogram in Adobe Lightroom.
A (non-)secret connection
We’d like to show you a little trick in Lightroom. It is not limited to the newer 3.x versions—it’s also available in earlier ones.
The picture’s light levels can be specified directly using the histogram at the top right section of Developer. We’re talking about the light levels that can be controlled using the Exposure, Recover,Fill Light, and Blacks sliders, a little below.
The histogram, as you may know, shows the hue distribution of the picture. The left side shows occurrence frequency of the darkest pixels, and progressing towards the right, the number of lighter and lighter ones. According to this, Lightroom’s histogram is divided into 4 parts:
The leftmost, pretty narrow section represents the darkest picture parts, close to black, so it corresponds to the areas which are enhanced by the Blacks slider.
The next part, about twice the size of the previous, stands for darker areas, those that are not completely black but shadowed, darker than mid-gray, which sometimes need a little lighting. This is the field for Fill Light, which brings brightness to shadows, but affects highlighted areas to a lesser degree.
The third, largest section is occupied by midtones. Basically, this area controls the brightness of the picture as a whole, excluding the darkest and lightest parts. It is the equivalent of the Exposure slider.
The last part, small as well, stands for highlights. The most frequent task here is the taming of runaway whites, the adjustment of burnt-out areas. This is what the Recovery slider does.
How does it work?
It’s easy as pie. Just bring the mouse pointer over the histogram part you want, and the section will be displayed a little lighter. Also, a small black two-headed arrow will appear above it. Under the graph, section name and value will be displayed (e.g. Exposure -1,74). The selection will also be highlighted below, on the value field related to the corresponding slider.
Click and drag the section to the left or right to adjust slider value. That’s all!