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stress that you want to measure is on the list for not being sensitive to Fv/Fm, it is
suggested that Quantum photosynthetic yield of PSII be considered. It is sensitive to
most types of stress listed
Running the Fv/Fm test
The last file used for this type of measurement will open up and a small screen will
appear within the larger screen. It will show the file name and ask if the file is to be used
and if one wants to proceed to measure with this existing file, and the parameters that
have been set in the existing file. The other option is to create a new file by pressing
Change.
Fv/Fm measuring Screen
Press “proceed” to use the existing file and “change” to use a different file.
A second box appears and asks if you want to add measurements or “append” the loaded
file, “cancel” and go back to the main menu, or “overt” overwrite the last file entirely.
To make a measurement with the default settings programmed into the OS1p at the
factory, place the end of the fiber optic bundle into a dark clip that is being used to dark
adapt a leaf.
Slide open the black slider, and press the red button near the end of the fiber optic
bundle. This will trigger a measurement. Measurements may also be triggered by
pressing the measure button on the measuring touch screen. (The PAR clip is not used for
Fv/Fm measurements). If a warning appears that says the fluorescent signal is too low,
the modulated light intensity must be adjusted. (see the next section).
