Photoshop: Quick and Dirty Depth of Field Effect

Creating a shallow depth of field effect is a feature included in almost every 3D modeling and rendering program, but the effect can add valuable processing time to the rendering process. 3D rendering programs are excellent at recreating accurate depth of field effects based on distance from the POV. When effect is more important than accuracy, a quick Photoshop session can duplicate a shallow depth of field.

In this example we'll be working with this image:

We're looking to create a depth of field effect with the straw and the front edge of the glass in the sharpest focus. After opening the image in Photoshop, I'll switch to 'Quick Mask' mode (type 'Q') and using a brush with a very soft edge, paint a mask over the areas that should be sharpest in the final image. Varying the opacity of the mask as I get further away from the focus plane will improve the final version of the effect.

Once I've painted the mask, I'll switch back to 'Standard Mode' (type 'Q') and execute the 'Lens Blur' command (Filter->Blur->Lens Blur...). Varying the 'Radius' value effects the amount of blur applied to the unmasked areas of the image.

Clicking OK to accept the filter's action produces the final result.