OPERATION OF THE JUNIOR-PAM
CHAPTER 5
5.6.3
Box (16) - Light Parameters
<SAT-Pulse>
The typical maximum (level 12) PAR value is
10000 µmoles/(m
2
·s). 12 different intensity
levels are available with level 1 corresponding
to about 70% of maximum saturating pulse
intensity. Pulse width can be adjusted from 0.2
to 2 seconds. The <SAT-Pulse> defaults
(intensity level 12 and 0.6 seconds pulse
width) work well with most samples that is the fluorescence transient
reaches a plateau and does not drop at the end of the saturating pulse in-
terval.
<Actinic Light>
12 actinic light levels are available. At a distance of 1 mm from the tip
of the 400 mm JUNOIR-PAM light fiber, the values for PAR of the <In-
ternal PAR> list (in µmoles/(m
2
·s)) apply. Note that damage to the light
fiber or long-term used LEDs can decrease light output by the JUNIOR-
PAM.
<Far Red Light>
Different from saturating pulses, width of far red illumination is adjust-
able between 2 and 30 seconds and the 12 far red intensity levels regu-
late intensity from 10% (at level 1) to 100% (at level 12) of full power.
The default values for intensity and far red illumination (level 10 and 6
seconds, respectively) work well with most leaves. During adjustments
of far red illumination, the effects on the level of Fo´ fluorescence needs
to be observed carefully and short illumination periods should be pre-
ferred over longer ones.
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