GFPIII operation manual
Opti-Sciences, Inc.
using five to thirty measurements.
Median
is the final option. Here, measurements from two to thirty can
be selected and the Median is reported after the measurements are taken.
For most applications, the instrument is now ready to make measurements.
Other options include the ability to change the Gitelson chlorophyll content equation for direct readout in
chlorophyll content values. The Equation worked for Elm, Beech, and Wild Vine. However, this option
provides maximum flexibility in case researchers want to make adjustments for other species. These
values can be changed by tapping the
Chl+CFRx
windows.
The Gitelson equation used is
Chlorophyll in mg m
-2
= 634*F
735
/F
700
+391
from Gitleson (1999). For
more information see the Gitelson (1999) paper.
You are now ready to make measurements.
For measurements with the leaf clip:
Place the end of the fiber optic completely into the leaf clip and tighten the Allen screw so that it is snug.
Place the sample in such a way that it is located directly under the middle of the end of the fiber optic.
The fiber optic aperture does not have to be completely filled by the sample. Tap the
Measure
box.
It takes
five seconds to make a measurement
. The Ratio and direct chlorophyll content values are
displayed along with the sample number and the number of measurements left before an average is
reported. (This is true when one of the averaging or median modes is being used). CFR: is the ratio of
fluorescence or fluorescence emission at 735nm / 700 nm. Chl: is direct read out of chlorophyll content in
mg m
-2
according to Gitelson’s equation.
Pts Lft
is the number of points left before an average in
displayed. The larger yellow box displays the measurements that have been made to calculate the average
value. One can scroll through the values with a finger or a stylus if larger numbers of samples are
averaged. Measurements may be deleted by tapping the
Delete
box.
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