This is one of over 4720 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
A brightness & contrast adjustment that modifies only the lightness channel of the image preserving the original colors. Can be very useful for photographers.