I recently ran across a how-to on producing a Tilt-shift camera lens effect in Photoshop. While reading it, I decided to redo the tutorial for those people who use, or want to use GIMP.
The original photo (already cropped down):
First, we want to increase the saturation of the image. How much it is increased depends on the desired effect and the source image.
For my example, I increased the saturation to 60.
We will also increase the contrast a bit.
For the example, I found 20 to be a good setting.
Now that we have the base layer situated. It is time to work on the next layer. The second layer will start off as a duplicate of the first in its current form. Right click the first layer and select “Duplicate Layer”.
The purpose of the second layer is to hold a blur. We will now apply the blur to the layer. Before doing this, be sure the new layer is selected. You may also wish to name this layer something other than the default, do this by double clicking the layer name.
When in the Gaussian Blur dialog box, adjust the radius to something between two or three, all the way up to ten or so. The larger the resolution of the base image, the larger radius you want to use. Even with saying that, please play around to determine which works best for you and your photo.
Now that we have the blur applied, we want to set it so that the original shows through at one area. This will create the final product’s focal point.
In order to accomplish this, we will create a layer mask on the second layer. Right click the layer and select “Add Layer Mask…”.
Leave the dialog box with the default setting of “White (full opacity)”.
We will apply a blend as the layer mask. Select the Blend tool, and check the settings. Gradient should be set as shown, and Shape should be set to “Bi-linear”.
Drag over a portion of the image to create a blend. This will be applied to the mask, so where the blend is added, the first layer will show through.
Tip: Use Ctrl as you drag to keep to fixed degrees.
If it doesn’t look as desired after the first blend, feel free to try again, as a new blend will overwrite the older one.
There are many examples of photos like this on the web. Some were done using a fancy (and expensive) lens on an equally expensive camera, and others were done digitally with Photoshop, or now GIMP. I look forward to seeing your creations in the comments!