So why do we need spot colors? Well, we as humans can see a wide range
of colors. Scientists claim we're capable of seeing
10 million shades. And if that sounds like a lot consider
that some animals, such as tropical fish and birds, can see colors we can't.
And in fact bees can even see into the ultraviolet.
Of course, we're not trying to print the ultraviolet, we just like to print the
colors that we want to see. But there's a limit to what we can print.
Now, this sort of odd shaped rainbow that you see is supposed to represent the
range of colors that we can see. Admittedly, you see a limit there that
defines what we can see on a monitor, so clearly we're not seeing everything that
we can see. But this is really just to give you an
idea of what the capabilities are. The monitor gamut is reasonably big, the
CMYK gamut is pretty much smaller, although you'll notice that there are
some parts of the CMYK gamut that actually fall outside the monitor gamut.
Colors like cyan, you really can't render faithfully on a monitor, you can come
close, but you can't quite hit it. And then of course, we have the PANTONE
gamut which is wider than what we can see in either other reality,
the CMYK or the monitor. And, I'm using PANTONE here but there are
other spot color systems. But the concept is the same.
These are specially mixed inks that let us accomplish stuff in print that we
couldn't with a combination of CMYK. Now CMYK is adequate for photographic
reproduction for the most part but there are a lot of colors that we really like
that we can't print within that gamut. Now there are some colors that you could
print equally well using spot colors or using CMYK.
For example, and I just pulled this at random.
PMS 235, you can approximate very closely with CMYK.
But then when you come across colors like bright oranges or navy blues, you're
going to find that you really can't print those satisfactorily with combinations of
the process inks. And we tend to like those bright colors,
and if you want to image those bright colors, you're going to have to use a
spot color. And navy blue, very common problem.
Think how many logos you know of that use navy blue.
That always goes kind of grey, a little bit purple.
You really can't do it with CMYK. If you want navy blue, you're going to
have to use a spot color. And then, of course, if you want to print
something like a metallic ink. Or fluorescents, or neons, you can't even
come close in CMYK. So, that's why we need spot colors.
We need to be able to create a special ink that accomplishes a color that we
have our heart set on, that we cannot approximate with CMYK.