PhotoPlus X2 User Guide - Serif

70 Manipulating Images
The vertical Y axis is the relative pixel count at each of the 255 levels on the X axis
described above. The higher the graph is at any level, the more pixels reside at that
particular level. Remember that this histogram could refer to a Red, Green, Blue,
RGB or luminance channel.
A crosshair cursor lets you move around the histogram, displaying the pixel count
for the colour level that your cursor is currently placed at. For example, the tab
opposite shows the cursor at colour level 18 (see the first peak), which has a count
of 829 pixels.
You can choose to view the histogram for an individual Red, Green or Blue
channel, or the composite of the three, the RGB channel. Luminance (or lightness)
can also be shown.
To view a specific channel:
• Click the Tab Menu button at the top right of the tab to reveal a flyout. To
change to a different channel, pick a channel from the list or display statistics
(as shown above) by checking Show Statistics.