One way to access the Curves Adjustment Layer is to go to the bottom of the Layers Palette and click on the circle that’s half gray / half black. The entire list of Adjustment Layers will pop up. Navigate to Curves and the Curves dialog box appears. An alternate way to bring it up is to go to the Options bar at the top of the Photoshop workspace, navigate to New Adjustment Layer and then to Curves. Regardless of the path you choose, a new layer will appear in the Layers Palette called Curves 1.
The dialog box that appears on your desktop will look like this (I took the liberty of outlining three key components with red squares that relate to the adjustments of the photo in this Tip of the Week):
The sky in the sunset photo is rendered too bright, yet there’s detail throughout the histogram. I based the original exposure on the foreground that was in shadow to prevent the introduction of noise in the dark areas of the capture. This dictated the sky had to be darkened in post processing. To darken it, I pulled down the white point in the Curves Dialog box in addition to moving the shadow slider to the right to richen up the sky tones. I then used the “finger” tool to make fine adjustments to the sky’s midtones and bright blue areas. The beauty of this tool lies in its simplicity of use. Simply move it over a section of the picture you want to impact locally. Click and slide the tool upwards to lighten a given area or move it down to darken it. It’s an often-overlooked feature of Photoshop that should be used by more photographers.
I adjusted the settings so the sky took on more drama and appeared the way I remembered it when it was photographed. The problem is that the adjustments left the shaded foreground too dark. The beauty of an adjustment layer is that it’s accompanied by a mask, so parts of the adjustment can be hidden. The brush tool set to paint with black can be used to hide the darkening effect of the correction to the sky. Click on the brush tool in the tool bar, and at the top of the workspace in the Options Bar, set the opacity to 50%.
Begin painting over the photo with the brush to restore the “proper” foreground exposure. Once accomplished, the corresponding layer mask will appear black and relates to the areas that were painted.
The final result is a photo with a corrected sky that is in keeping with the original exposure of the foreground. The technique is not restricted to a sky/foreground scenario. Anytime part of a photo needs darkening, but you don’t want to impact other key components, use a Curves Adjustment Layer to apply the darkening effect to the overall photo and paint it away from areas you want to restore to their original exposure.