User's Manual

Table Of Contents

6.2.2.1. Histogram

While color correcting or adjusting exposure, the histogram can be a

great help. A histogram is a graphical representation of the tonal

values of your image. This graph illustrates how the pixels in the

image are distributed across brightness levels. In other words, it

shows the amount of tones of particular brightness found in your

photograph ranging from black (0% brightness) to white (100%

brightness). Ideally, well-balanced images will have tonal values across the entire range of the histogram.

1. To read a histogram, start at the left edge, which shows the shadow regions. The middle shows the

midtones (where most adjustments to an image are made), and to the right are the highlights.

2. The histogram is able to display Red, Green, Blue channels separately or, by default, shows all of

them at once. Click on the Histogram to switch between seeing a composite Histogram or just

viewing details about the Red, Green, and Blue channels (which can be useful for spotting tint issues

and color casts). You can also see a grayscale average for luminance.

3. Additionally, clicking the two small triangles in the upper left and upper right corners will show hot and

cold pixels respectively. These are pixels that have shifted or exposed to become absolutely black or

white pixels.

• Cold Pixels. To enable or disable the a warning mode for absolutely black pixels, click the

triangle on the left of the histogram. Absolutely black pixels will be displayed in bright blue in

the image. Cold pixels (in blue) indicate areas where black has achieved maximum

concentration (a zero value).

• Hot Pixels. Clicking the triangle on the upper right will show where your image is completely

white, where the histogram is clipped on the right side. Absolutely white pixels are displayed in

red.

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