User manual

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CLICK Pro User Manual
v. 1.0
In the example, the pixels that have the lowest value are not at the top left, and the
same occurs with the highest values, but with the top right. This means that the whole
dynamic range offered by a digital image is not being leveraged, and not all the possible
values are being used.
In the following image the adjustment cursors have been moved manually towards the
parts of the graphic where information already appears. The effect is to afford the image
greater contrast or “depth”.
This tells the program that the “form” or information from has to begin practically at zero
and end practically at the value of 255, i.e. the horizontal axis is compressed so that in actual
fact the image increases its dynamic range.
Thus, all the pixels of the image are distributed towards new values up and down the
brightness axis, thus gaining pixels in dark values and pixels in light values.
Remember that images will practically always have thousands of pixels or dots, and the
lowest values of the vertical axis will not be seen.
It will not always be necessary to adjust the cursors to such limits. Very often it will only
be necessary to get close enough to obtain a good result if you wish to avoid an image with
saturated or “burnt” brightness. To do so, look at the image all the time as you move the
cursors to control the effect of the expansion of the dynamics.
It is possible to adjust the middle point of the histogram, too. The middle point works like
“gamma”. It represents where is the limit between dark and bright values. Moving the middle
point means compressing one side and extending the other side. If you move it to left, you
are making the image brighter, because you are making the bright side bigger, and opposite
occurs moving middle point to right.
The Auto Histogram button can be used to move the cursors automatically to
adjust the dynamics of the image. It can work fine on most images, but usually
is necessary to readjust manually the three points to obtain the desired result.