A few years ago I finally got a genuine
GretagMacbeth®
ColorChecker® for
my birthday! This chart is an important tool for serious
photographers and film developers. It provides a set of
known reference colors which can be used as a setup and adjustment
standard in film and video production.
This is a fairly good HTML approximation of
a Macbeth Color Checker. After comparing it to the
real thing, I found the hues were fairly accurate but my computer monitor
has a little too much chroma intensity. The same HTML page looks very
different when displayed on any number of dissimilar monitors. (Try it
yourself.)
New!
Here are the RGB values for
the Macbeth Color Checker.
Macbeth Color
Checker Analysis and Predictions by Joan Moh, Hon Mun Low, and Greg Wientjes
at Stanford U.
The gray scale on the
bottom row indicates clearly when a photo is under- or over-exposed. In this
picture the first three squares on the bottom row appear a little too
similar. The bottom row of the chart has four very different
shades of gray between a white square and a black one. So this picture,
taken with a "surprisingly affordable" digital camera,
appears to be a little overexposed. The chart is sitting on my scanner,
and is about to be scanned!
Here
my lovely assistant demonstrates the proper use of the chart, standing
in the middle of our vast suburban acreage. Really, the only place
I've ever seen the Macbeth chart in use is an occasional single frame in the leader
of a 16-mm film, in which a lady is shown holding the chart for an additional example
of realistic skin tones.
Here is another web page
of people holding Macbeth Colorcheckers.
 This
is the scanned chart. Conversion to JPG format didn't help the image much,
but this is another test for which this chart is well suited. The Macbeth chart
is supposed to be kept in its package, in a plastic wrapper which is
inside a cardboard sleeve, in order to keep it clean and keep it in
the dark! Long term exposure to light would bleach the colors,
apparently.
The Macbeth Color Checker is available through a number of internet outlets.
I got mine through the mail from Edmund
Industrial Optics. You might
try Amazon. But
of course the internet has numerous other sources including
this one,
this one
and this one.
Also, just as interesting,
the ColorChecker Three-step Gray Scale Card
and the ColorChecker White Balance.
You'd better buy a ColorChecker while you still can.
More GretagMacbeth
layoffs. The dismantling of GretagMacbeth's facility in New Windsor continued yesterday
[10/27/2006]. More of the color-management company's 60 employees were laid off, as the office prepares
to close down.
GretagMacbeth ColorChecker®: The
GretagMacbeth ColorChecker® has been around since 1976 when it was called the Macbeth ColorChecker®.
Originally proposed by C. S. McCamy, H. Marcus and J. G. Davidson in 1976 as a test for
photography, television and printing, it is still being produced and used for a variety of color tests and color
profiling.
ColorCharts Lab Report.
GretagMacbeth Color Checker Numeric Values.
Technical discussions of the Macbeth Color Checker, seen on other web sites:
The Gretag Macbeth Color Checker is an array of 24 printed color squares, which include
spectral simulations of light and dark skin, foliage, etc. The Color Checker is used for
precise color balance when shooting color film. 9:13 proportions will fill a 35mm frame.
Scientifically engineered to ensure true-to-life images, the ColorChecker cards are
designed to help you recognize, evaluate and adjust colors quickly and efficiently.
Uses include photography, graphic arts, electronic publishing and television.
*
One of the most photographed images in the world, the ColorChecker is a unique test pattern
scientifically designed to help determine the true color balance of any color rendition
system. It allows you to avoid costly mistakes by checking for potential problems.
ColorChecker DC is specifically designed to meet the needs of digital photography. Users can
check and compare the digital reproduction of a real scene or a test pattern, make a white
balance with a digital camera, or use the chart with camera profiling software to create
an ICC profile of your camera.
GretagMacbeth is an international leader in color management tools. A
related company, Gretag Imaging, is in the high-end of color digital printing equipment.
*
The Macbeth chart seems somewhat reminiscent of "Farbe Kontrolleur",
the
classic work by Sue E. Generis (1899-1963).
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