Brush Tool (B).
The Intensify's Brush tool is a powerful painting tool. It works like a traditional drawing tool by applying the effect in a selected area by painting it in. Use the brush tool to selectively adjust your image. Click and hold your mouse and drag the brush on the area of the image that you want to be affected.
Erase Mask (E).
The Erase Mask allows you to remove an effect that has been applied to the image, or alter the shape of the mask before the effect is applied. Use the Erase Mask to selectively edit your image. Click and hold your mouse and drag the brush over the area of the image you want the effect to be removed from.
Clear: Selecting this button will clear the mask you have created.
Invert: After you paint the area that you want to affect with your edit you can easily select the “Invert” button to invert your mask.
Show: Selecting the show button will show the mask you have created in red.
The Size slider: Controls the size of the brush in pixels. Use large size brushes for editing large areas of an image and use smaller size brushes for detail work.
The Opacity slider: Controls the strength at which the brush is painting. At an opacity of 100, the brush will apply the effect at 100%.
The Softness slider: Controls the edge of the brush. A softness of 0 will produce a hard edge line when brushing, and a softness of 100 will have a feathered or a transition edge when brushing.
Click and drag the center point of the Gradient Tool to position it and drag the top or bottom lines to adjust for the top and lower gradients. Change the Exposure for example and press the Apply button to place the effect on the image.
The Gradient tool and mask can be altered using the Angle and Opacity controls. The Angle option will precisely rotate the gradient mask to the angle which you desire. The Opacity control will control the maximum amount of the effect applied.
When the Opacity control is set to 100, the gradient will transition from a full effect to no effect. When the Opacity control is set to anything less than 100, the gradient will transition from a partial effect to no effect.