Professional Histograms

Professional Histograms is an advanced function to adjust the levels. It helps you to adjust the entire tonal range of an image. You can also use Professional Histograms to make precise adjustments to individual color channels in an image.

Enter the function:

Click button 'Exposure' on function bar, then select 'Manually adjust' or select from its popup menu.

The interface and the description:

The first step after you enter this function is to select the channel and the number of control points.

In the combo box 'Channel' when can see there are four channels can be selected: RGB, R, G and B. Select the channel you want edit.

The second step is click button '3', '5' or '7' to get control points. The more control points you select, the more flexible you can do.

After the upper two steps, we can see the curves appear in the window. The histograms are shown below it. See the following figure:

Histograms are diagram to show the statistical number of pixels in different color value. The gradient bar from left to right shows the value from black(0) to white(255). The vertical gradient bar in left means the output value from black to white. The default curve is a diagonal with 45 degree means the value of current channel keep unchanged.

Now, we can drag the small control block to change the map of value between input and output. Drag it up, the corresponding curve segment move up, and the corresponding brightness increases. On the other hand, drag it down to decrease the output brightness. May be you have noticed that the block is changed like this after you drag it. The left half part means the input value, and the right part is the output value.

Click button to make a smooth curve or not.

Click button , you can peek a color from the original photo. A line with an arrow links the color with its brightness value in histograms.

Click button 'Auto' in RGB mode to get the same result as 'Auto Contrast' , click it in separated R, G and B mode to get the result of 'Auto Level'

'Save as color theme': Save/Append the current curve to a color theme file.