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There are lots of ways to make a photograph
look like a painting. Here's another one that simulates painted
strokes by blurring dark areas of the image and sharpening
lighter areas. It takes just a few steps and works very well
with landscapes and other images that include lots of detail.
STEP 1
We'll first want to work with the image's darker pixels, the
shadow areas. To select the shadows, Command-click (Mac) or
Control-click (Windows) on the thumbnail of the RGB channel in
the Channels palette, then invert the selection. You can invert
a selection with the keyboard shortcut Command-Shift-I (Mac) or
Control-Shift-I (Windows), or with the menu command Select>
Inverse.
When you Command-click or Control-click on
a channel, you make a selection of each pixel in the image
according to its brightness in that channel. (We're using the
composite channel RGB to select according to the image's overall
appearance.) Any pixel that's pure white is 100% selected, any
pixel that's pure black is 0% selected, and all other pixels are
partially selected according to their luminosity. Compare the
two images below. The original image, top, contains a simple
black-to-white gradient. Below, we Command-clicked the RGB
channel to select according to luminosity, then filled with red.
As you can see, the pixels that had been white and very light
gray are red, while the darkest pixels are not noticeably
changed. Observe that the selection marquee indicates pixels
that are at least 50% selected, but that pixels darker than 50%
gray are also partially selected.
STEP 2
After making and inverting your selection, use the keyboard
shortcut Command-H (Mac) or Control-H (Windows) to hide the
selection border, the so-called "matching ants." Now apply a
Gaussian Blur. The full image is shown above, with a portion of
the image visible below at 100% zoom. (As always, it's best to
evaluate an adjustment or filter at 100% zoom.) To open a second
window of your working image, use the menu command Window>
Arrange> New Window for [filename]. Depending on the amount of
fine detail in your image, a Gaussian Blur or between 1 and 2
pixels is usually sufficient.
STEP 3
Invert your selection again or Command/Control-click on the RGB
channel thumbnail once more. This re-selects the lighter pixels
in the image. Again, use the shortcut Command/Control-H to hide
the selection boundary. Use the Sharpen> Unsharp Mask filter.
The settings Amount: 200%, Radius: between 3 and 5 pixels, and
Threshold: 0 are usually sufficient, depending on the content of
the image.
STEP 4
Apply the Texture> Texturizer filter to finish the effect.
Adjust the sliders to suit your image. (In this example, the
Canvas texture was applied with the settings Scaling: 70%,
Relief: 3, Light: Top Left.) Compare the "before" and "after"
close-ups in the following images.
Keep in mind that this
technique is best used with images containing lots of detail. It
is less effective with photos that contain large areas of
reasonably even color, such as portraits. |