Nikon Labophot Instruction Manual page 25

Failures Causes
)
Actions
• Low contrasT in
). To increase contrast optically, select phase
specimen
contrast. darkfield, or differential interference
methods.
• Specimens should be stained a rather dark color, if
possible.
• In color photography, depending upon the speci-
men, red-blue separation staining (Mallory or Azan methods etc.) is preferable to red-violet combina- tion staining (H-E staining).
• In black-and-white photography, for low contrast
specimens a film of finer grain and higher contrast
is more suited (such as minicopy film).
• For general specimens a film of wider latitude and
finer grain is preferable.
• Insufficient N.A.~. Use a large N.A. objective.
resolving
of objective
• For the same magnification, increase power of
objective rather than that of eyepiece to attain
higher resolution and sharpness, even though depth
of field is reduced.
Excessive magnifi-~. 500 - 1000 times N.A. are magnification limits for
cation
resolving power.
• Extraneous light~. Darken the surroundings or place the cap on the
flare
entering the ocular ocular finder.
fi nder
• Stray Iight entering
-----+.
Take care not to expose microscope and specimen
to direct sunlight and other intense lights.
• Inadequate use of-----. Select best filter combination.
graph
filter
obtained
• Film of another
•• Note that, when using a daylight film, remarkably
make or emulsion NO.
different spectral sensitivities will result depending
upon the type, make, etc.
• Even though of same make, according to emulsion number, different color rendition will be obtained.
Wrong power
• • Take picture in every case at the specified voltage.
source voltage
(Refer to P. 16)
• Incorrect exposure---->. By inadequate exposure time, color rendition will time
not be true on account of "reciprocity law failure"
Then, with the help of exposure time indicator, adjust exposure time according to characteristics of film by means of NO filters, or compensate for such fai Iure by means of CC fi Iters. ( Refer to Kodak Data)
) • Especially, for making color prints, it is recom-
film development
mended to contact the development laboratory.
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