One of the
sheer joys, to me, of owning a microscope is that I am capable
of sharing what I see with others through the use of photomicrography.
It is quite satisfying to acquire personal knowledge of a subject
or organism but it is much more satisfying when that knowledge
can be shared. I dabbled in sketching my observations for a few
years and came to the conclusion that I needed to find a different
avenue of recording my observations. When Paramecium takes
on the appearance of an amoeba, well then, the accuracy of my
drawings may be called in to question! Needless to say I needed
another way to record my observations.
I have had
a lifelong love affair with photography, so it was only natural
that I turned to using the camera to record my observations. Mind
you, I am not a scientist attempting to record scientifically
accurate images. I am just an ordinary guy wanting to share what
I see with my friends and colleagues. At first I made my images
with color transparency films. This was OK for a while but started
to get expensive. Transparencies would have color casts and I
would have to add color correction filters to the light path to
eliminate the color casts in the transparencies. Basically, a
roll of film would be shot, processed, inspected, and reshot if
necessary. My rejection pile of transparencies rapidly exceeded
my "keepers" pile. Because of the necessity of reshoots,
this was getting expensive! The cost of the color transparency
film plus the cost of processing was adding up. Sure, I bought
my film in "bricks" so that I would have consistent
color reproduction for a while but transparency film is very touchy
when it comes to exposures and this made for the need to bracket
my exposures. Improperly exposed transparencies outnumbered properly
exposed transparencies 3:1. I needed a better film for my needs.
A few years
ago I tried some color negative print film. I reasoned that it
was much easier to hand around 4" x 6" color prints
for people to view than it was to drag out a slide projector and
screen for a slide show or to force people to view 35mm transparencies
on a light table with a focusing loupe. Frankly, I was unimpressed
with the results. Machine-made color prints still had color casts
to them depending on the care in color correcting the prints exercised
by the person operating the printing machine. I was also disappointed
as to how little contrast and color saturation the machine-made
prints recorded. I could have hand-printed photographic enlargements
made but this ran into quite an expenditure, too. I shelved this
idea and continued to photograph my subjects using color transparency
I turned my
thinking around when the digital revolution hit. I purchased a
dedicated film scanner for my professional photography and decided
to go back and scan some of my older color negative photomicrographs.
After a little experimentation I found I was able to make scans
of the negatives that competed fairly well with the scans of my
transparencies. Scanning the negatives and manipulating the images
in Adobe Photoshop® allowed a great deal of leeway in removing
color casts as well as creative cropping and selective sharpening
of an image. With the advent of photo-quality inkjet printers
I could make relatively cost effective prints of my negatives
to share with my friends and colleagues. I decided to take another
look at using color negative films for photomicrography.
Today I use
color negative print films almost exclusively for photomicrography.
I have found several advantages in doing so. First, color negative
emulsions have come a long way in terms of color saturation, contrast,
and sharpness. Older color negative emulsions had coarse grain
compared to color transparency films. Today's color negative films
are approaching as fine emulsion grains as color transparency
films. The ability of today's color negative films to capture
fine image details has been improved by an order of magnitude
as compared to color negative films of just a few years ago. Color
saturation and contrast have been greatly improved, too. Today's
color negative films have greatly extended exposure ranges as
compared to color transparency films.
A second advantage
to using color negative film is that the exposure latitude of
print film is greater than the exposure latitude of color transparency
films, especially when image tones approach the lighter end of
the exposure scale. As little as 1/2 of an f. stop in exposure
error can spell the difference in having details in lighter image
tones or losing those details when using color transparency films.
Color transparency films generally have an exposure range of approximately
5 f. stops from pure black to pure white in a transparency. Color
negative films expand that range to approximately 7 1/2 f. stops.
This is an advantage in recording those lighter image tones. Whereas
with color transparency films if you overexpose the light tones
any image detail is lost in those tones, if you overexpose color
negative films, the details are still recorded on the film and
the details can be retrieved with a little extra work with the
films must be exposed carefully to retain details in the highlight
areas of the images. Because the exposure latitude of color transparency
films is so limited, details in darker image tones can be rapidly
lost, too. However, with color negative print films having an
extra 1 1/2 f. stops to 2 f. stops extra latitude, more highlight
and more shadow details may be captured in the image than can
be captured using color transparency films. This becomes especially
important when scanning the images with a desktop film or flatbed
scanner. Desktop scanners have limited dynamic ranges (the ability
to record slight differences in tones in highlights and shadows
of an image) and the best images to scan are those that contain
maximum details in both the highlight and shadow areas of the
image. My film of choice for photographing crystals through my
microscope is Kodak Gold 100 color negative print film. This emulsion
is almost too saturated for general photomicrography but is just
what is needed for recording the colors of crossed-polarized crystals.
In fact, the color saturation of this emulsion is greater than
my scanners ability to record the colors produced by the negatives!
of making photomicrographs on film cannot be ignored, either.
A 36 exposure roll of Fujichrome Velvia 35mm color transparency
film costs about $4.50 US per roll under the best of circumstances.
Processing the color transparency film will cost, on average,
$5.00 US per roll. Some labs charge more, some labs charge a little
less. Cost per image then becomes about 27¢ US per image
if there are no reject images due to exposure errors. If
you keep one image for every three images you make in a bracket
of exposures, then the cost per image rises to .79¢ US per
image. Color print film, on the other hand, may be purchased for
considerably less. I purchase 24 exposure rolls of 35mm Fujicolor
Super HQ color film for $4.99 US for 4 rolls in a pack of film.
This works out to $1.25 US per 24 exposure roll of film. Processing
only for a 24 exposure roll of color negative print film will
cost, on average, $2.50 US per 24 exposure roll. If all
of the images are "keepers" then the average cost of
an image on color negative print film is approximately 16¢
US per image. I average about 18 keepers per each 24 exposure
roll of print film. My final image cost works out to about 21¢
US per image. This is nearly 1/4th the cost of using color transparency
films! This allows me to make 4 times the number of images on
my limited film budget.
I can hear
some of you already thinking that the costs I have presented do
not include the costs of making prints from the color negatives.
That may be true but keep in mind that my "final" purpose
is a digital image, not a physical print. Whether I make my images
on color negative films or color transparency films, scanning
these images to make digital image files requires the same amount
of time and effort. It becomes a "wash" as far as scanning
expenses go. If I want a physical print of either an image from
a color print negative or from a color transparency image I would
use the same output devices for either type of film.
output, I sometimes print the scans of my color negatives on a
photo-quality inkjet printer. Passing around small 4" x 7"
or 5" x 7" prints is still an easier way to view my
images than setting up a slide projector and screen and is much
better than having a bunch of people crowding around a computer
monitor. Today's inkjet printers are truly amazing and the output
rivals photographic prints in many ways. Having a "digital
darkroom" allows for ultimate control over all aspects of
the image's appearance. I have printed my favorite images as 11"
x 14" prints and hung them on my walls. Visitors to our house
cannot distinguish these prints from my many other photographic
images spread throughout our home.
If I need
a transparency made from a scan of a color negative I use one
of the many "digital darkrooms" advertised on the Internet.
If I need slides simply for projecting on a screen I have slides
made at Color
Services in Santa Barbara, CA, USA. I send them the image
files and they send me excellent, 4k 35mm slides for $8.00 US
per slide. If I need reproduction grade transparencies I use a
local professional photo laboratory that outputs image files with
a Kodak LVT film recorder, the best in the business! Of course,
these come at a much higher cost!
Fuji has introduced the Fuji Aladdin ADPC IV Digital Photo
Center in many department stores and drugstores. The Fuji
Aladdin Digital Photo Center allows photographers to input images
off of Cd's or digital camera memory cards and make prints of
their images as either wallet-sized, 4" x 6" or 6"
x 8" sized prints. Rather than printing a large group of
4" x 6" prints on my inkjet printer to hand around to
my friends I will save the image files to a CD-R disk and print
them out on the Aladdin Digital Photo Center printer. Prints are
made on specially coated Fuji papers and are nearly indistinguishable
from regular photographic prints. The quality is very high and
the cost is extremely reasonable. Our local Walgreens Drugstore
charges a mere 29¢ US for a 4" x 6" print!
color negative films are Fujicolor Super HQ ISO 100 and Kodak
Royal Gold ISO 100. For general photomicrography I will use the
Fujicolor film. The images of the copepod nauplius and Paramecium
accompanying this article were made on Fujicolor color negative
film. The images of magnesium sulfate crystals were made on Kodak
Gold 100 color negative film. The Kodak Royal Gold is a fine emulsion
for very saturated subjects but is a little too "brutal".
I rarely expose
these films at the rated ISO settings. Camera meters don't seem
to analyze a scene lighted by backlighting, even though the subject
is transparent, as they would a scene lighted by reflected light.
I have found that most cameras have a tendency to overexpose these
films when used for photomicrography. When using the microscope's
tungsten Kohler illumination system I rate both of these films
at EI 200 or EI 300. With both films I have to adjust the color
temperature of the light with an 80B filter to yield daylight
temperature lighting. The 80B filter also makes a fine filter
for visual observation. When I use a modified electronic flash
as the light source, I dispense with the 80B filter (the electronic
flash is already daylight temperature) and rate both films at