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Digital imaging has made leaps in popularity since the first
digital cameras appeared five years ago. Digital cameras are
quickly gaining on conventional film cameras in sales among
the average user. By using a digital camera, a person can produce
an image that a computer translates into a "series of
notations or bits of information" (Krejcarek
4). The camera’s ease of use, speed, and controllability
are a few factors that have contributed to its popularity
(Butkowski 14). But the professional or amateur photographer
may be interested in knowing how well the digital camera is
able to capture color in comparison to a film camera. In this
paper, I will primarily deal with this subject. But first, I
will discuss exactly how a digital camera composes a visual
image in comparison to a film camera.
It should be noted that digital cameras and film cameras
go through a few similar steps in order to produce an image.
Both use a camera lens to focus incoming light. Also, they both
use shutter speeds to control the length of time that light
enters. Finally, they both capture the image on some kind of
"light sensitive medium" (Butkowski
21). Once the light is captured, the two cameras use
different methods to create the image. In order to produce color,
both have to record the individual wavelengths of light they
receive and somehow use that information to portray different
colors. The difference between the two cameras’ methods has
to do with the kind of light sensitive medium that each uses.
A film camera creates black-and-white images by capturing the
light on a light-sensitive material coated with silver-halide
molecules. These molecules react with the light to become areas
of black metallic silver and form an image on a negative. Color
film contains dye layers in addition to the silver-halide layer.
Each dye layer is sensitive to certain intensities of light,
whether the light is blue, green, or red. Color images are produced
by pairing each layer on the film with a dye layer of the exact
opposite color and then adding transparent dyes that produce
a positive image. The addition of these dyes forms the positive
by subtracting appropriate colors from the transmitted light
(Butkowski 21).
The digital camera goes through a quite different process
after it captures the light for the image. The light-sensitive
medium used by digital cameras is called a charge coupled device,
or CCD chip. The chip is used to measure and record light
energy inside small storage spaces called pixel areas. The light
intensity is measured by means of electrons being freed from
the CCD chip when light passes through it. The electrons are
drawn together by a positive charge that is applied to the electrodes
in the pixel. The brighter the light is, the more electrons
that are drawn together. Then, the CCD chip converts
the light intensity information into digital values corresponding
to the number of electrons in each pixel. This information is
stored either in the memory of the camera, or on a removable
disc or cartridge. Once this is done, a computer can read the
digital information, convert the digital values in the pixels
to colors, and reproduce the image! (Butkowski
22)
Now that we know how each type of camera creates the image,
the question is: "Which camera does a better job of accurately
capturing color?" In terms of resolution or image detail,
a 35-mm film camera still outperforms the consumer digital camera.
Most consumer digital cameras come with a CCD chip of either
2 or 3 megapixel resolution, referring to the amount of detail
that the chip can handle. According to PC Magazine, the
low-end "digital cameras still aren’t fast enough or
crisp enough to handle every shooting opportunity that comes
along(PC Mag 180)." The acuteness
of the resolution is still better with film
(Krejcarek 29). However, professional photographer Joel
Butkowski points out that some high-end digital cameras
can match or exceed the quality of film, capturing 40 million
pixels of information in comparison to the 25 million pixel
resolution of the 35mm slide film (Butkowski
18).
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An advantage that Butkowski emphasizes is the increased image
control that the digital camera allows which leads to improved
color accuracy. He uses the example of pre-testing film in order
to check for any color casts inherent in the film. This is usually
only done by photographers who must have a very accurate portrayal
of color, perhaps for a clothing catalog. Since, certain types
of film are noted to produce "either warm or cool tones",
each color layer in the film must be tested to see if one color
is more dominant. If a color imbalance in the film is recognized,
a color-correction filter must be placed over the camera lens
to compensate for the color cast. This entire process may take
an entire day to complete, but there will always be a color-shift
variation of about 2 percent to 5 percent. On the other hand,
digital cameras have built in software that automatically balances
the color to remove any color casts. Even if the automatic color-balancing
doesn’t produce the desired accuracy, the user can simply look
at the monitor and make necessary adjustments right after the
picture is taken (Butkowski 16).
The color manipulation that digital photography allows
is a definite advantage over conventional film for the creative
photographer. In a matter of minutes, the user can use an image-editing
program to change the background color, create linear or radial
blends from one color to another, and even convert black-and-white
photographs to tones of a certain color! (Krejcarek
81) This allows a person to experiment without worrying
about the cost of film. Images can be copied without losing
resolution (Krejcarek 8). Any unwanted
changes that are made to an image can simply be undone using
the editing software. This allows the photographer to become
more of a designing artist.
Currently the best consumer, low-end digital cameras seem
to be the 3-megapixel cameras. The are reported to take "excellent
still photos in well-lit, daytime scenes" (PC
Mag 179). However, due to the higher level of detail
of the average 35mm film camera, film is not dead by a long
shot. Therefore the consumer that is concerned with getting
a crisp, high-resolution shot is probably better off sticking
to film. But for those who want to be able to manipulate the
color of their images after the shot is taken, digital
cameras offer a decided advantage in error correction and creativity.
1975
Works Cited
- Butkowski, Joel, and Andra Van Kempen. Using Digital
Cameras. New York: Amphoto Books, 1998.
- Krejcarek, Philip. Digital Photography – A Hands On Introduction.
Albany: Delmar Publishers, 1997
3. "Digital Cameras – Is Film Dead?" PC Magazine.
7 Nov. 2000: 179.
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