Download DarkAdapted 3.0.1 for Mac from our website for free. This software for Mac OS X was originally produced by AquilaDigital Partnership.
From the developer:
DarkAdapted is an application program. It controls the amount of red, green, and blue in your screen gamma so that you may, for example, preserve your dark adaptation while using your computer. Gamma fades can be scheduled, AppleScripts may be scheduled, and system-wide hotkeys can be set up to execute AppleScripts and gamma fades.