User manual

11 • Modifying an image
ColorQuartet 5.0 Pro
104
Densitometer tips
• If no change seems to take place: The changes you type into the Densitometer window will
take effect based on which color tool you have open at the time. In some cases, only a few pix-
els may be affected; this may make it appear that no change has taken place in the image.
• Multiple reference points: You can define any number of reference points in the image by dou-
ble-clicking on the feedback windo
w. A red cross indicates the active reference point; green
crosses indicate the other points. To delete a point, simply click on it and then press the com-
puter’s backspace key.
• Moving between points: You can move back and forth among the defined reference points in
the feedback window by using your computer’s tab key or space bar, or simply by clicking
once on the desired point. Each time you move to a new point, the read-out in the Densitome-
ter window changes accordingly. This lets you check whether changes made to one part of the
image also affect other parts.
• Comparing original and new values: The original image values and proposed new values – for
both LCH, RGB and CMYK – are shown in the Densitometer window simultaneously, making it
easy to evaluate changes before implementing them. You can type new values directly into the
Densitometer window, or you can work in the various color tool windows and observe the
resulting changes in the Densitometer and feedback windows.
• Determining the number of pixels measured: The measurement “kernel” can be set at point
sample (1 pixel), 5 pixels, 9 pixels, 21 pixels or 37 pixels. The larger kernels are particularly
useful for measuring large areas with the same color or for getting an average read-out from
an area with varying color.
• Automatic location of extreme points: If you click on the small colored squares in the Densito-
meter window, ColorQuartet will automatically locate the lightest point in the image, the
darkest point, or – for R, G, B, C, M and Y – the point with the most saturated color. The lightest
and darkest points are defined in relation to the L* axis of the L
CH color space. The most satu-
rated points are defined in relation to chroma in the LCH color space. The points found will
depend on the size of the measurement kernel (i.e., the number of pixels measured).
• Viewing color separations: To view each process color individually, choose C, M, Y or K from
the menu at the bottom of the feedback window (PC: click with the right-hand mouse button
to access this menu).
• Viewing RGB results: If you are working in RGB, you can view each of the three colors individu-
ally by choosing R, G or B from the menu at the bottom of the feedback window (PC: click with
the right-hand mouse button to access this menu).