Selective Layer Adjustments
Photoshop CS3 Tutorial
How to Make Selective Layer Adjustments in Photoshop
You may want to add an Adjustment Layer that only affects certain areas. It may be a portrait where you want a bit more light on one side of the face.
This method is commonly used to paint light into or out of an image.
Open an image in Photoshop (File > Open).
Click the Adjustment Layer icon and select Curves.
Click in the middle of the curve and drag the new point up slightly. The entire image lightens. Click OK.
Notice that the Adjustment Layer Mask is white. It affects the entire image. Click to select the mask and press Cmd/ i (PC-Crtl/i) to change the mask to black. The image is back to normal.
Select the Brush tool. Set the color to white and lower the opacity. Paint the mask with white to lighten the image in specific areas.
At any point, you can double-click the Adjustment Layer icon to access the curve and change the settings.
To soften the mask, select the mask and choose Filter > Blur > Gaussian Blur.