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[SG] Photography (Part 1)

Dear Gentle Gardeners,

Many of us are interested in garden photography.  On the Daylily list, a
member asked the question: "What is the best film to use to get true color
in flowers?"  Tim Fehr,  one of the list owners,  responded to this
question and has graciously permitted me to share it with you.

 He does request, however, that you contact him before using this
elsewhere. I hope it will help you in your photographic endeavors. It has
certainly given me some ideas.

Tim's letter begins:
First off, films are formulated primarily to render good skin tones, not
flower colors. Secondly, films age and color shifts as the film 'matures'.
This is more critical in slides than prints since a lot of sins can be
corrected in printing.

For slides I recommend using Kodachrome 64 slide film.  The Kodachromes are
dyed during development and this is a very stable color process.  All other
slide films have the dyes already incorporated into the films, these are
less stable as a result, making for greater differences between rolls, even
from the same emulsion batch.  Also, the E-6 develpment process is more
prone to color shifts itself.  I used to work in a film lab and we balanced
the E-6 machines twice a day, but many labs do this only once a week
depnding on volume of film processed.  The films being sent through
'consume' certain dye couplers depending on what colors appear on the
films, so colors naturally shift as rolls are processed. If things balance
out, and they often do, then adjustments are minor. However, I remember
after an air show we developed roll after roll of blue sky shots with tiny
planes and the blue skys shifted to purples as the day progressed despite
our correction attempts.  There are perhaps only a dozen Kodachrome labs in
the US so the process is tightly controlled; any corner photolab can set up
and process E-6 so the quality tends to vary depending on how good the lab
staff is and how closely they monitor the process.  You can even get kits
to develop E-6 slides at home.

Exposure too is critical for good color. If your camera is fully automatic,
you are at its mercy.  The problem is in the meter. Almost all cameras
today use reflected meters - that is they meter how much light is being
reflected back from the subject.  The meter is calibrated to average an 18%
gray, halfway between black and white.  If your photo is of an 'average
scene' the meter does a very good job.  An average scene contains some dark
areas, some lighter areas and generally these two balance out.  However,
some flowers are far from average.  A near white, up close, reflects more
light than 18% so the meter will underexpose this shot to get it to 18%.  A
dark red, purple or near black will absorb more light, thus it reflects
less than 18%. In this case the meter calls for more light to bring the
picture back up to 18%, resulting in overexposing these colors.  There are
a number of ways to work around these problems.  The easiest and least
expensive is to buy an 18% gray card at a photo store.  Place this card
just in front of the flower, in the same light and meter.  Lock the meter
reading in, and remove the card, ignore any changes in the meter settings
as these are the result of the 'non-average' scene.  In the absence of a
gray card, the palm of your hand reflects back a constant amount of light
too - place your palm in front of the flower, meter off of your palm and
then open the f-stop one stop (your palm reflects roughly twice as much
light as the gray card, this adjusts for that difference.)  The last way to
work around this is to use an incident light meter.  These meters use a
translucent plastic dome to meter how much light is hitting the subject,
not how much is being reflected back from it. You place the meter in the
same light as the flower and read to find out what your exposure should be
for that amount of light. You then manually set the camera to the same
f-stop - shutter speed combinations it recommends.

In slides, even slight underexposure makes the colors more intense
(saturated) (National Geographic typically underexposes slide films
intentionally to make the colors richer, not necessarilly truer, but this
often makes more dramatic photos.)

In print films you have compound issues.  Even if you expose the film
properly, today's computer controlled printers will try to 'average' the
scenes, correcting your manual exposure corrections.  For example, you
shoot a white daylily, exposing it using a gray card so that the white gets
to be white (actually this part of the picture is overexposed, but that's
what makes it go white after all)  The printer however, sees that part of
the film as overexposed and tries to correct for that - tries to bring it
back to 18% gray.  You need to be aware that color and exposure can be
greatly controlled by the printer.  Don't be satisfied with color prints
that aren't true to color or are too dark or too light.  If you find a good
photolab and explain your concerns they will often work with you to achieve
the best color and exposure for any photo.  They have no idea what the
color of a daylily should look like after all.  If you don't tell them it's
too red, too green, too light, too dark, more cream than tan, etc. they
can't correct for it.  Photo lab folks are trained to produce good flesh
tones, and they can adjust easily when someones skin appear too green or
blue, but they just are clueless as to what color your flowers should be.
(I've sat in the printing chair, let me tell you you get real good at
guessing, but then you guess an awful lot!) Don't be afraid to tell them
they are off, just explain how you thing each one can be improved.  If you
want to really throw panic into a photolab, include a gray card in your
photos and lay the gray card on the counter and compare the color and
difference of too light and too dark - it's a pure test of how well they
are doing and it can rattle them pretty good.

Print films also age and shift colors as they do so.  Heat is your worst
enemy, leaving camaras in the car or even outside on a hot day can effect
color shifts in your films.

Another factor is that films come in different batches, each may differ
slightly as to their sensativity to light.  When I attended the Nikon
school they intructors were National Geographic photograpers.  National Geo
buys whole lots of the same emulsion batch, shoots test rolls and then
labels that batch as to color corrections and exposure corrections needed.
Most of us don't have that option, but it makes you think.  (Remember too,
film is manufactured, aged, cut and packaged all in total darkness, how
many other products that we buy haven't been visually inspected <G>)

Another issue is artificially enhanced color films.  Kodak's current Gold
print films are slightly color enhanced. (So is almost every amatuer print
film actually, it's what sells. People generally, given the choice of
accurate color or more colorful photos, usually want the more colorful,
thus accuaracy suffers.) I remember when these films were first introduced,
they still made the more accurate color flims, but we like many stores quit
carrying them since they accounted for such a small percent of sales.  <TO
BE CONTINUED>
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