There is a function available in various photography applications that can often be overlooked. The function I am referring to is the "Lens Corrections" button.
The photograph was taken about 30 minutes north of Santa Fe, in Chimayo, New Mexico.
In the first image, the photo is opened without any corrections.
By simply turning on "Enable Lens Profile Corrections", Adobe Camera RAW can correct for any wide angle lens distortion, unwanted vignetting and other potentially unwanted artifacts.
One of the great advantages of digital photography is that every photo has information embedded in it that contains what camera was used, the exposure, and what zoom you used pertaining to a specific lens. Photoshop uses this data and can automatically correct for potentially unwanted effects from shooting with a wide angle lens.
For more information and detailed explanations:
Adobe Photoshop for Photographers
with Josh Withers
July 8 - July 13, 2012