Using Masks and Curves in Photoshop CS2/CS3
The object of the lesson was to use selections and then painting on masks to effect Curves emphasis on specific parts of photos. I picked two of my own.
Photo 1
This photo was taken of a statue in the late afternoon. The picture was intentionally underexposed (Ev-2) to make the statue darker. I had a homework assignment for a group I lead in Photoshop Elements to lighten only the statue and not the background. This was the picture I took for them. The original photo is shown next. Click on the image for a larger picture.
In Photoshop Elements, I would add a Levels layer, select the brush tool and paint over the statue while making the Levels adjustment to brighten the statue. (The same would work for Photoshop). However, in this lesson I learned that I can use a Curves adjustment layer for that brightening that targets areas of the statue more accurately. This is the mask I painted on the Curves layer. I used a low Opacity brush around the edges to smooth the transition between the statue and the background.
I adjusted the Curves layer using two points, as follows.
The end result is a brighter statue that stands out from the background. Again, click on the image for a larger version.
Photo 2
I took the second photo of Pikes Peak, Colorado on an overcast day slightly before sunset. The exposure settings were on auto, and the mountains and sky were washed out with the bushes in the foreground underexposed.
I redid this image in three steps.
1. I used the Magic Selection Wand to select the bushes in the foreground. Then I added a Curves adjustment layer and moved the curve to brighten the bushes.
2. I used the Inverse of the bushes selection and added a Curves layer to let me darken the mountains and the sky.
3. To place extra emphasis on the mountain/sky I added a duplicate of the last Curves adjustment layer and painted over the darker clouds to reduce the intensity of the addition of the third curves layer. In doing this I was able to bring out the colors of the sunset much better.
In each case I used a light opacity brush to smooth out the transition between the bushes selection and the mountain selection on the masks.
The Layers palette looked like this after completion.
Here are the images after the three curves layer additions:
1. Mask and curves on the bushes.
2. Mask and curve layer added for the mountains and sky.
3. Final Curves layer with mask for mountain/sky and touchup for emphasis. The mask for the last layer of the final image was the following.
And the image was.
I might have pushed it too much on the last layer, but the image looks nice on my monitor. However, it may be darker than most people's preferences. All in all, it was fun.
