How to use aperture to get a nice blur effect. The depth of field can make a picture go from normal to amazing. Try using this to better your photos, this website has a lot more helpful information. -JPH
Aperture Vs. Depth of Field Visual Guide » Expert Photography
Autumn tree: I like the angle of this shot because it enhances the trees large size. Additionally I like the shallow depth of field, focussing the lower leaf yet enhancing its colour with the out of focus background.
Download your free cheat sheet to help you get off AUTO and start getting more creative photos with your Digital Camera. IT shows you how you can control Depth of Field. It shows the best Aperture for Portraits and the best Aperture for Landscape photos. It also looks at another key factor in controlling Depth of Field: Focusing Distance.
I know how aperture works but it's nice to have a visual for the different ranges. - Aperture Depth of Field Comparison
How To Blur Backgrounds In Photoshop - Shallow Depth of Field Effect
In this video I’m going to show you how to create a blurry background in Photoshop (the shallow depth of field focus). We’re going to apply the blur by using the Lens Blur Filter which allows you to apply the narrow depth of field so that some objects in the image are in focus while others are blurred.