Photomerge

A photomerge is a combination of multiple images to make one amazing image.

This can easily be done in PS using the photomerge command:

The Photomerge command combines several photographs into one continuous image. For example, you can take five overlapping photographs of a city skyline, and then merge them into a panorama. The Photomerge command can assemble photos that are tiled horizontally as well as vertically.

The above image is a composite of 4 full resolutionpics:

1.  Select the files to be combined.

PhotoMerge is buried under File > Automate > PhotoMerge.  In the above pop-up dialog box, simply click the Browse and add the photos to be merged.  It is helpful to have Vignette Removal and Geometric Distortion Correction checked.  Blend Images Together will create smooth blends between the layers with masks.