Using the selector, you can select one point (Click), multiple points (Shift + Click), or designate a rectangular area in an image (Click + Drag). The area(s) you select will receive the adjustment, while the adjustment will be masked out of other color ranges. For instance, let’s say you want to make an adjustment to a blue sky. If you use the ‘Color Range Selector’ and pick an area in the sky that is blue, the adjustment will be constricted to areas in the image that match the blue color that you selected. You can further fine tune the mask by using the ‘Amount’ slider that corresponds with the ‘Color’ range mask options.
Let’s use the same blue sky example and say you used the ‘Color Range Selector’ tool to pick a blue area in the sky. By default, the ‘Amount’ is set to 50 and represents a good balance. If you move it to 0, it will narrow the color range, that means that only areas in the image that exactly match the blue color you picked in the sky will be affected. If you move it to 100, it will broaden the color range, that means that additional hues similar to blue will be affected, not just the specific blue color you originally selected.
Let’s look at an actual example. In the below image, I wanted to add some brightness and contrast to the sky, but not the rest of the image. Here is the original image: