December 5th, 2007 Retouching - How to use blur in a creative way
You may have heard the term “short depth of field”. What this essentially means is that a very select portion of the photo is in focus. Sometimes photos have foreground elements that are in focus and background elements that are out of focus; this is a photo with a short depth of field. These photos are much more interesting than photos with a long depth of field.
So what happens if you’re not sure how to set the depth of field on your camera, but you want that same effect? Well first, I’d highly recommend reading up on how to work with your aperture to achieve this goal, but in the meantime, here’s a quick Photoshop tip.
In this photo, we have a longer depth of field. You can still see clear edges of the trees in the background, and the foreground is also in focus. We are going to use the blur tool to simulate a shorter depth of field.
The blur tool is in your tool palette. Go ahead and select it as shown above. Now, we need to change the blur settings. This looks very similar to the brush tool - you can choose your diameter, hardness, etc. We want a very soft brush here because we don’t want it to be clear where we’ve blurred and where we didn’t - things should blend together. I typically start with 0% hardness and try it out. If it’s too little, then I increase the hardness and try again.
I also typically start at a strength of 70%. This allows me to see a big effect when I use the tool but not so much that it looks fake. When you use the tool, you can always go over a blurry area over and over to increase its blur, so don’t worry about it not being blurry enough the first time. This is another thing that you can change based on what image you’re using, so feel free to try an even lower strength and change it through trial and error.
Now it’s time to create some blur. Just like you’re painting with a brush, click and drag on an area of the photo to blur it.
I painted on everything in the background - all of the trees and the fence. Here’s the result:
As you can see, it makes a difference in the image. You can make it more subtle or more flagrant - it depends on the photo and what your style is.