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Rangefinder Magazine
November 2001/Features
The 10 Facts of Life About Color Correction Part ll by
Will Crockett
Long before the days of Photoshop, commercial shooters had to take full
control of correcting color problems before the shutter clicked. Trying
to get the green shift out of a fluorescent light source, adding warmth
to a cool main light, or bringing up the color temperature of a chandelier
by having an uncorrected transparency “fixed” in the scanning
process was a big and very expensive ordeal. Today with the mass of photographers
rushing to digital capture as a profit-generating medium, color correction
before the exposure is being employed as a great way to make better quality
images—and make them faster than Photoshop. As you will see, correcting
color before the exposure is not as complex as you may think, and it will
produce much better results than any electronic method.
No matter if you shoot digital capture, color neg, or color transparency
films like me, you will see a major refinement in your color reproduction
capabilities after you discover the Ten Facts of Life About Color Correction.
Color Correction ToolsFact #4—Always trust your exposure meter.
As photographers, is there any tool we count on more than our exposure
meters? A solid exposure is the foundation of good color reproduction
in any medium. The only way to get predictable, repeatable and accurate
color values from your film or digital capture chip is to provide an accurate
exposure for them. You don’t really need to spend a fortune on the
latest and greatest flashmeter meter to get good exposures, but you will
discover that a “premium” flashmeter will permit you to light
your set with more ease, accuracy and confidence. Choose a meter that
has the features that your needs, that will handle flash and ambient light
blended together, and seems comfortable for you to use as you will need
to become fluent in using your meter for daily use. We recommend any of
the five following meters as excellent choices for your daily and critical
work: Gossen Luna Star F2, Gossen Starlight, Sekonic L-508 or L-608, Sekonic
L-358 and the Minolta Flashmeter V. I personally have all of these meters
and know they are all excellent weapons in the battle against exposure
gremlins.
10 facts of life about color correction:
• Color Temperature and Color Balance are not the same thing.
• Know what color your strobes really are.
• Most white photo fabrics and papers aren’t white and some
glass is not clear.
• Always trust your exposure meter.
• Always trust your color meter.
• Never trust your color meter.
• Never, ever trust the Polaroid.
• Know where your film’s neutral rendering point (NRP) is.
• Filters are precise, gels are not.
• If you’re not sure – schedule a pre-shoot to test. |
As long as we are talking about exposure,
let’s open up the can of worms regarding how to measure for exposure
with a meter. For most applications when photographing people, you
will get the most accurate exposures by programming your meter with
the film speed printed right on the box (most pro films really are
the speed they print on the box nowadays) placing the meter in the
point of the scene where you want your most accurate exposure, then
pointing the dome of the meter directly into the lens, not the light
source. You can use this method (recommended by all the major meter
manufacturers, by the way) for each light individually, or all the
lights at once. Most exposure problems you may have can be solved
by using a good quality, properly calibrated meter used by aiming
the dome right into the lens. It’s really that simple –
I’ve been doing it for 20 years with great results.
Fact #5—Always trust your color meter.
Color meters measure the color of light and present the data in terms
that a photographer can use. For a commercial or industrial shooter,
they are a Godsend however, they’re expensive, fragile, and need
a little interpretation. The two big brands are Minolta and Gossen.
Both are very good and both are around $1000. The other brand available
in the U.S. is the Broncolor meter which is no better than the other
two at “color metering” but it can measure flash duration
and permits some nifty adjustments with Broncolor’s high-end
strobe packs (big boy toys!) but costs a lot more money and not as
easy to use. We recommend Gossen’s Color Pro 3F and Minolta’s
Color Meter IIIF because they both handle flash and ambient light
well without any adapters, they permit you to measure both ambient
and flash at the same time by programming your meter with your selected
shutter speed, and they give you readings in the Kodak Wratten scale
so that you can just read the meter and it will display the appropriate
filter to use. Older meters like the popular Minolta II give you readings
in the international standard “mired” scale, which means
you have to convert your color meter readings to the Wratten scale
by using this wacky chart glued to the back of the meter. Also, the
newer version 3 meters are much more accurate and are clearly worth
upgrading to if you’re using the Minolta II or the Gossen 2.
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Color meters measure two separate qualities of light color, the color
temp (actually the averaged color temp) and the color balance between
the red, green and blue components of the light being measured. That’s
all. They do not measure exposure values. You can trust your color meter
to give you very accurate color temp information in most situations, BUT…
Fact #6— Never trust your color meter?
Even though color meters will measure color temperature very accurately,
they have a tough time with color balance. That’s the bad news. The
good news is that they are off by a predictable amount. Here’s the
rule to fix the problem, we call it Will’s Add Half Rule—and
you use only on color balance measurements, not color temperature measurements.
Here’s what I mean—when your color meter suggests to use a 20M
filter, add half! Half of 20 is 10; 10 added to 20 is 30. Therefore, use
a 30M. Under 95% of all lighting situations, this is your color correction
value. I know it sounds weird, but it’s true when using most of the
popular color transparency and negative films. Digital capture is a different
ballgame, where some cameras are very sensitive to the green fluorescent
shift and some are not. So just like everything else in the photo world,
here comes the disclaimer: test this out for yourself before you shoot
it on a job!
The “add half rule” equals add 50%, and we’ve found that
Kodachrome, some Agfachrome, and some film your brother in law makes from
tree bark have not been tested by us. Please contact me with your results
if you use these films when you test. (but keep the tree bark stuff, please).
What do you do if you can’t get at a color meter? First, find out
exactly which type of light source you’re planning to correct. Then
make a decision on what film(s) you’ll be shooting, and get a copy
of the film manufacturer’s suggested filtration data sheet. It will
tell you which filters will match your film to your light. Where do you
find the filtration data sheets? Contact your film dealer, or the film
manufacturer’s rep for your area. They should be able to get you
whatever you need. We keep the current Fujifilm color filtration data
for transparency films available on our website: www.shootSMARTER.com.
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Color Temp: Neutral
Color Balance: +45Green
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Color Temp: Neutral
Color Balance: +15Green
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Color Temp: Neutral
Color Balance: Neutral |
The above represent an example of changing the color balance while retaining
neutral color temperature.
Fact #7—Never, ever trust the Polaroid.
Polaroid’s color instant print films are great for what they are
designed for. We use Polaroid’s ProVivid and PolaPan 100 to check
our camera system for any sign of malfunction, to see the composition
of our shot, and to look for errors like a cord or light stand in the
frame or in the reflection of a pane of glass. Polaroids are not a substitute
for an exposure meter, nor a color meter. In fact, one of my assistants
has a big sticker on his personal Polaroid back that states, “This
is NOT a color meter.” One major reason why is that Polaroids (daylight
balanced films) can suffer from reciprocity failure when they’re
exposed at times longer than 1ž8 of a second. And, depending on the type
and storage of the Polaroid film, when they fail, they shift green. So
if you shoot a “ ‘roid” on a color correction job at shutter
speeds slower than 1ž8 second, be aware that some, most, all of the green
you see isn’t really there. Use your color meter, and the “add
half rule” to determine “real” green shifts.
Sometimes on a shoot you will be pushing the limits of what the Polaroid
is designed to handle in terms of exposure and color rendition. In these
instances you will find a “conflict” between what the meter
is indicating and what the Polaroid is showing you. Please keep in mind
that the meter is right 99% of the time and to never, ever trust the Polaroid.
Will Crockett is an award winning commercial photographer and considered
one of the country’s top seminar presenters and photo educators.
Based in suburban Chicago, Will has an impressive client list that spans
the globe to include DaimlerChrysler, United Airlines, Sears, ABC Network
Television, and Boeing just to name a few. You can learn more about Will
and his work at www.shootSMARTER.com.
Next issue: PART THREE: Applications
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