Hitachi CHROMASTER 5160 Instruction Manual page 302

3.2 Utility Setting
NOTE: When MICRO is set for GAIN, energy level may
reach the upper limit of measurement or A/Z
OVER RANGE may be caused when auto zero is
executed. For a wavelength where light quantity
is large or when a difference in light quantity is
large between sample and reference sides, you
should set NORMAL for GAIN.
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