Likewise, just because we can do something doesn’t me we should do something. If all your friends jumped off the roof and broke a leg would that be a road not worth traveling? Yes. Or, one man’s steak is another man’s hamburger. Which I take to mean ‘different strokes for different folks.’ That brings me to Black Light.
It Does What?
Not long ago I walked by a co-worker’s iMac and noticed the screen was, well, different. Not everyone sets up a Mac’s screen for proper gamma and brightness levels vary based upon ambient light and the discriminating visual requirements of each Mac user.
So, I paused by the cubic entrance and asked, with all seriousness, ‘What’s with the Mac’s screen?‘ What I got was a quick lesson in why some roads are less traveled, and why choosing a road carefully is an important aspect of life.
The Mac was using a utility called Black Light which puts special visual effects on the screen. It does this by manipulating the gamma curve.
Black Light can display an inverted screen whereby blacks and whites are reversed. Think of it as a negative of what’s displayed on the screen. It can also introduce an overexposure effect which replaces white grays with white which helps to remove some white and light gray stripes.
Of course, Black Light can simulate a color filter (the kind that some Mac users put in front of their screens to reduce glare). That’s what my co-worker was doing.
Finally, Black Light can also adapt an image for the standard 16-235 luminance range which is used by HD televisions when the Mac is connected by HDMI. Anyone who’s ever had to use an adapter to get HDMI to work will know.
Each of the effects can be toggled on and off with a click to the Dock icon or the Menubar icon. Black Light has been around for years and I’ve bumped into more Mac users who have than I expected; especially considering what it does.
See? Different strokes for different folks.