Ocean Optics OOIBase16 - Manual (Page 9)

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seconds), a dialog box opens with a running countdown of the time left before data acquisition begins. At
this point during this countdown, you can click “Start Now” to override the delay. Also, when the data
acquisition begins, you can always cancel the procedure, which results in a loss of data.
By selecting Update Graph During Acquisition, you can see the live spectra being acquired but the
acquisition may take longer. If you select Acquire Data as Fast as Possible, you will not be able to use
your computer for any other tasks while the time series acquisition is running.
This dialog box also requires that you choose an Acquisition Mode. If you choose Absorbance or
Transmission, a dialog box opens requiring you to take a reference and dark spectrum – even if you have
already done so.
Subtract Dark Spectrum
This command subtracts the current dark spectrum from the spectra being displayed. This command is
useful if you are trying to look at a change in an emission spectrum or are trying to eliminate fixed
pattern noise from the spectra. The Subtract Dark Spectrum function only acts on the spectra displayed in
Scope Mode.
Data Acquisition
This command opens the “Configure Data
Acquisition” dialog box (see picture at right).
It allows you to specify data acquisition
parameters. The choices made in this dialog
box control all channels in your system.
Trigger Mode allows you to choose between
four modes of operation. The Normal mode is
a continuously scanning mode. The Software
mode is an external control mode allowing you
to signal the spectrometer to take complete
data sets. The External Sync mode allows you
to control the integration time from an external
source, such as a periodic TTL signal. The
External Trigger mode is ideal for use with
laser and other short-pulse events; however,
this mode has a fixed integration time of 55
milliseconds.
The first 24 pixels in the spectrometer do not respond to light but they do produce an electrical signal.
When you select the Correct for Electrical Dark Signal box, this function subtracts the value of these
optical black pixels from the entire signal, reducing the counts of the black pixels to almost zero.
Choosing the Correct for Electrical Dark Signal function does not replace the Store Dark
Spectrum function.
You would only select the S2000 Strobe Enable if you were operating an external strobe source. To
purchase one of our strobe light sources, such as our PX-2 Pulsed Xenon Lamp or our LS-450 Blue LED
Pulsed Light Source, contact an Ocean Optics Applications Scientist.
Samples for Static Average is a signal averaging function that averages x number of spectra before it gets
to OOIBase. The value chosen affects all channels in the system. The higher the value, the better the S:N.
The S:N will improve by the square root of the number of scans averaged. Samples for Static Average has
no limits; thousands of scans can be averaged if you are patient enough. (Another function averages spectra
after the scans get to OOIBase. See
Data Analysis on page 10.)