hardWare calibration

No matter how seriously you take this software calibration malarkey,
there’s always going to be a weak link in the process—worryingly, it’s
the human eye. Even if you have perfect vision, the eye just isn’t an objective judge of color balance or consistency. Take that classic shadow
on a checkerboard optical illusion. Stick a Photoshop color picker on
both squares and  it’s clear they’re exactly the same shade, but our
pathetic noggins just won’t see it. To get around the problem and calibrate your screen properly, there really is no alternative but to splash
out on a robotic eye. But fear not, as you can pick one up for $100 or
less. It won’t look like a prop from Terminator, though. Pity.
The device in question is related to what car body repair shops use
to match paint colors during a repaint. This nifty little gadget is usually
about the size of a mouse and only requires a USB connection. Simply
hang it over the top of the screen so it rests in the middle of your monitor, where brightness tends to be at its best. Then, corresponding sof tware flashes various colors over a period of several minutes for the
all-seeing eye to detect. This then feeds the color data back to the sof tware so it can create a custom Windows color profile for your monitor.
More advanced colorimeters can even read ambient light levels to tell
you the optimal brightness for your viewing conditions.
Colorimeters aren’t the only hardware you can use for monitor calibration. Spectrophotometers look pretty much identical and do  the
same job, but they can also calibrate your printer because they’re capable of analyzing both light emitted from monitors and light reflected
off printed color swatches. The only downside is price, as spectrophotometers usually cost considerably more than hardware dedicated
solely to monitor calibration.

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