This is one of over 4626 effects generated by Filter Forge, a Photoshop plugin that allows you to create your own filters.
To open this filter, you must have Filter Forge 1.0 or higher installed on your computer. If you don't have it installed yet, click here to download Filter Forge
This snippet shows how to zoom an image as if using a magnifying glass: the inside is zoomed, the outer edges not.
zoom sphere spherical distortion zoom snippet magnify