Enlargeability
It has often been stated that there is no limit to the
enlargement factor, since larger prints are viewed from
greater distances. Fine, if there is a barrier preventing
the viewer from approaching closer than the intended
distance, or if the intent is obvious as in photo murals.
When, for the intended viewing conditions, and audience,
the print gives a hint of UNINTENDED
lack of crispmess or granularity, or loses its maximum
visual impact, the limit has been exceeded.
Although we like to herald the virtues of the 8x11mm
Minox, and it is indeed a magnificent machine, there is an
enlargement factor for each negative at which the
characteristics of the print will reduce the impact of the
image. This break-up is generally signaled by an increase in
"fuzziness" or an increased awareness of "granularity" or
lack of smoothness. The former is the realm of the camera,
the latter, of the film. The perception of these factors is
influenced by the viewer's vision and experience.
The contact print (enlargement factor = 1) provides print
quality not possible with ANY degree of enlargement.
Enlargement introduces image degradation, the degree
depending on the AMOUNT of
enlargement. So, all other factors being equal, prints made
by enlarging various sized negatives TO THE
SAME DEGREE, should exhibit the same quality
characteristics. It is the AMOUNT of enlargement that
counts!
The Minox camera uses a special cartridge with an
un-perforated strip of film approximately 9.4mm wide, as
shown in the "contact proof" below. The size of the negative
image is 8mm x 11mm. The full image shown is approximately a
14 x enlargement with the fishing boat "Kiaora" further
enlarged. The fully enlarged boat is therefore a 120 x
enlargement which would produce a 38" x 52" full print. This
does not imply that I can make a 38" x 52"
silver print directly from a Minox negative
(the grain visible in the 16x20 inch print renders this
image unacceptable at that size), only that the information
to produce the image shown is present in this
micro-negative. The 120 x enlargement is 400 pixels wide on
your screen, and represents a 1.17mm wide portion of the
11mm negative. It clearly shows the silver grain clumps in
the background hillside, the worst case, middle gray haze in
a silver print. This image was made with a Minox IIIs and
now discontinued Kodak High Contrast Copy Film (5069), a
wonderful film with a nice spectral response and very fine
grain ... about ASA 6. The camera was hand-held at probably
1/60th of a second. The image demonstrates the spectacular
design characteristics, quality, and depth of field of this
fine 1950s camera.
The scale below the 120 x enlargement may be used to
appraise the resolving power of the camera/film combination.
I have no data about the "official" resolving power of
either film or camera.
The 14 x enlargement was made directly from a negative
scan. The 142 x enlargement was made from a "flatbed" scan
of a 16 x 20 inch silver print made with an Omega B-22XL,
Nikkor 28mm lens, and diffused light source.
When the 16x20 inch print is scanned at 600 samples per
inch, what are thought of as "grain clumps" (actually spaces
between grain clumps on the film), are in the range of 8
pixels across.
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