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Forrest M. Mims III
A few years ago George E. Hrabovsky
and I were discussing the most important tool in the
amateur scientist's toolbox. My vote was for the digital
camera, and I listed many reasons why.
George replied with only three words:
"The personal computer."
Of course George was right, and I discussed
why in this space on 12 November 2004 ("The
Citizen Scientist's Most Important Tool").
As noted then, the computer is indeed a superior tool.
After all, what use is a digital camera without a computer
to process, manipulate, crop, sort and store the images?
Because George is still right, let's
revisit this topic under a new premise: The digital
camera is the citizen scientist's most versatile instrument.
As I pointed out in the previous editorial
on this topic, the amateur scientist equipped with a
digital camera can photograph birds, tree rings, sunsets,
clouds, experiments, insects, flowers, tree canopies,
soil samples, surf, storms, bones, circuit boards, stars
and planets. Figure 1, for example, shows how tannin
leached from cedar elm (Ulmus crassifolia Nutt)
leaves strongly absorbs blue light and gives water a
red tint.
Moderately priced or even free software
allows the amateur to crop, enhance and archive thousands
of photographs on a computer hard drive or a stack of
CD-ROMs.
Amateur scientists can even perform
sophisticated analysis of their digital images using
ImageJ, the free yet powerful image analysis package
written by Wayne Rasband at the National
Institutes of Health (NIH). ImageJ can be downloaded
from the ImageJ
homepage. For some specific examples of how I use
this program, see "How
to Analyze Digital Images" (The Citizen
Scientist, 21 October 2005).
Since that 12 November 2004 editorial
appeared, digital cameras have continued to advance.
Today, many consumer digital cameras have a resolution
of from 4 to 8 megapixels. Cameras have larger liquid
crystal displays than in years past. They are also both
smarter and smaller. Battery life is greater. And many
technical advances have been made. Does your older digital
camera have an annoyingly long shutter lag after you
press the exposure button? Today you can buy a digital
camera for under $400 that captures an image in less
that 0.005 second after the camera has focused on the
subject.
Not only is the digital camera the
citizen scientist's most versatile instrument, it's
quite possible that the second most versatile instrument
is a second or third digital camera.
At solar noon every day the sun if
not obscured by clouds, my first digital camera, a 1998
1.3 megapixel Fuji, is used to photograph the solar
aureole and the sky over the north horizon. This camera
is still in use so images made today can be compared
with those made when this time series of photographs
was begun in the fall of 1998.
In 2002 I began using a 3.3 megapixel
Nikon 950 equipped with a fisheye lens to image the
entire sky. This time series is also ongoing.
In 2005 I bought a pair of Pentax Optio
water resistant cameras, the 3.3 megapixel WR3 and the
4 megapixel WR4. These cameras have internal focusing
and are completely sealed against dust and water. They
also have a very valuable function: elapsed time photography.
They can make up to 100 photos at intervals of from
10 seconds to hours. They are ideal for photographing
opening flowers, traffic flow, sunrises and sunsets
and clouds. (See my web
site for examples.)
Recently I acquired a Casio 7.2 megapixel
EX-Z120. This camera is not much larger than a deck
of cards. Yet this very fast camera features both automatic
photography and manual adjustments of shutter speed
and aperture or both. Thus, time exposures and images
with fixed settings can be made, both of which have
important scientific applications.
Some digital photographs made with
these cameras have been published in peer-reviewed journals
and various science publications and web sites.
The camera models mentioned above are
not meant to be endorsements, and the companies mentioned
did not provide the cameras. They just happen to be
cameras that I could afford at the time that best met
my requirements. There are many other outstanding cameras
at reasonable prices, and you can find considerable
information about them at web sites like Digital
Photography Review, Steve's
Digi-Cam and others.
What do you think? Can you think of
an instrument more versatile than the digital camera?
Do you have an outstanding example of a digital photograph
with a scientific theme that you would like to submit
to Gallery? Send your comments here
and place "Camera" in the subject line.
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