There are many artistic filter effects built into the capabilities of Photoshop, and many more can be purchased from third party vendors. What most of them have in common is that they make images look worse. Well, there is no accounting for taste, and that's my taste. However, there is one that I do like and actually use fairly often.  That is the posterize feature. Posterizing reduces the many colors of an image to just a few colors, making the image look like a paint-by-numbers painting, if you know what that is. The large patches of color can have a dramatic graphic effect. This verges on being art. I try to avoid indulging in art, but sometimes the urge cannot be resisted.

One of the situations that is irresistible is when you have an interesting well-composed colorful image that is wonderful, except that it is out of focus or blurred. It seemed like a great opportunity at the time, so you took the picture knowing that it might not come out sharp.

Posterizing using Photoshop is easy.  Bring the image into the full editor and from the menu select Filter > Adjustments > Posterize.  In the popup window, select the number of bits for colors. Usually 3 or 4 works best.

Saving Blurred Images

Here we are in Seoul, Korea staring down a great-looking lunch spread.  the lighting was fairly dim, so the lens was wide open and most of the image is out of focus. Still, the image seems to have some potential

posterized photo of lunch

Here is the posterized version of the image:

posterized lunch

Posterized images are inherently sharp because the middle shades showing the blur have been eliminated.  The details are lost and cannot be recovered by posterization, but at least there are sharply defined blobs rather than fuzzy blobs, and that is an improvement. Sometime retouching the image before posterizing will help the detail. Notice that in the original the metal cooking vessel has shiny highlights. Only a few of those highlights are preserved in the posterized version. Selecting the surfaces of interest and increasing the contrast would preserve them through the posterization. conversely, perhaps there is too much going on in the background. It may be better to downplay the background so it doesn't distract.  Lower the contrast or increase the blur with Photoshop to minimize the details. There is no need to be too careful in retouching before posterizing, as the posterization will cover a lot of sloppiness. Like I said, it is art.


Posterizing adds more punch to images that are already colorful.  Here is photograph of some fruit, before and after posterization.

Fruit original image   Fruit posterized image

The grapes in the original image are slightly out of focus and slightly blurred by camera shake. A pro photographer in a studio would never let that happen, but this photo was taken with a pocket camera under available light at a hotel breakfast. Posterizing adds sharpness and saturates the colors.

Posterize + Palette Knife

The Palette Knife filter often works well in combination with posterizing.  Select Filter > Artistic > Palette Knife. In the popup, try the sharpness at maximum and and the softness at minimum, and adjust the stroke length to suit.  Here is the posterized fruit with the stroke length at 4:

Posterizing + palette knife

The images from posterize + palette knife work well as backgrounds for titles or labels. The ordinary Photoshop adjustments to mute colors or contrast can be applied to posterized images to help title text stand out.