Editing Selected Areas- Part I
  by Dennis Wilkins


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With Picture Window Pro many transformations and tools may be applied selectively to parts of an image using masks. Masks provide amazing control, as we will see.
We will start with a typical situation. Hiking in the outdoors, you can observe many beautiful natural scenes, but what you perceive with your eyes, and maybe a good pair of sunglasses, may not be possible to capture directly with a camera. The scene below was photographed in Colorado’s Rocky Mountains on a partly cloudy summer day. The scene caught my eye because the intensity of the reflected clouds in the water contrasted nicely to the soft grasses.

Transform 2
The composition includes what I wanted, so no cropping was required. However, as you can see in the original download above, the clouds are not very impressive. It’s not what I saw when I was making the photograph. The dynamic range required to capture the clouds, grasses and flowers has compressed the clouds into a flat, dull image. The first thought one might have is to increase the contrast. This can be done with Picture Window using several tools, but the most comprehensive control is obtained using the Brightness Curve in the Gray Transformation.

Brightness Curve   The Brightness Curve tool can be applied to an entire image or to a selected portion of an image by using a mask. The window on the left shows a curve applied to a whole image (the small white box on the right of the Amount sliders shows what mask is being used – in this case there is no mask selected). The lumpy figure in the window is a histogram of tones in the image, from black on the left side to white on the right side. The histogram shows the relative amount of the image in any tonal range. In this case, the middle tone areas are most predominant, and there are tones from black to white, with only very small “near-white” areas.

The Brightness Curve enables you to move any tonal level of an image to another level, up or down. To increase contrast, you need to increase the slope of the brightness curve line. Moving the lower left corner of the transformation line to the right, and/or moving the upper right corner to the left can do this. Using this linear change causes dark areas to get darker (and possibly go totally black), and light areas to get lighter (and possibly go totally white).