Black Light

Apply special vision effects on your screen.

With Black Light you can apply a combination of visual effects to your screen by manipulating the gamma curve. Opening Black Light will automatically apply the selected effects. Quitting the application will restore the original settings.

Visual Effects

Invert Screen

Reverse blacks and whites, giving you a negative of the image on your screen.

Dim Screen

Reduce screen luminosity by dimming each pixel. Useful to reduce the luminosity of LCD screens beyond the minimal value of the back light.

Color Filter

Simulation of a color filter of a chosen color put in front of the screen. Lets you change the tint by setting the white point.


Replace white grays with white to remove stripes, making white the background of most windows. Ligher colors might change hue slightly.

HDTV Luminance Adjustment

Adapt image for the 16–235 luminance range used by some high-definition television sets when connected by HDMI. Normally, your computer should be capable of automatically adusting output values accordingly, but this isn’t always possible when the TV is connected through an adapter.

Combine them your way

Black Light’s simple preference panel let you combine effects with all the ease in the world.

Want a dimmed screen with a yellowish tint to help you sleep at night, here you go! A red-only inverted screen for your astronomy night, simple as a pie!

Always quick to toggle

You can toggle the selected effect combination by clicking on the Black Light icon in the dock. Or you can set a global hotkey. Or use the optional Black Light menu icon that can appear on the right side of the menu bar1.

Free Trial


OS X 10.6.6 Snow Leopard or later. Moving Black Light’s icon from the dock to the right side of the menu bar requires OS X 10.7 Lion or later.

For an earlier version of OS X (down to 10.2.8), use Black Light 1.7.1.

  1. The option to display an icon in the menu bar is only available with OS X 10.7 or later. 

Vision & Color Apps

  • © 2003–2017 Michel Fortin.