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Move an objective into the light path. Prior Scientific recommends the use of the highest
magnification objective that provides a clear peak maximum close to the top of the setup graph.
If a low magnification objective is used, further adjustments may be necessary when setting up
individual objectives.
It is strongly advised to maximise the size of the peak using the 45 degree
adjustment, then reduce the laser power.
Place the PF209 onto the stage and focus on either the coverslip sample or the mirror sample.
Use the digipot, in MAN FOC mode, to achieve focus.
Click Setup, which will open a graph that indicates the laser intensity over the PureFocus850
sensor. Adjust focus until a peak appears in the signal. At this stage, the peak may be very
small or may not be visible at all, even at high laser power.
If the peak is visible, slightly adjust the position of the 45
o
screw to increase the size of
the peak (Fig. 9).
If the peak is not visible at all, go to the mode menu and temporarily put the system into
slice mode. This will amplify the signal by a factor of 10, which may bring the peak above
the noise. If the peak is still not visible, adjust the focus to identify the peak. Adjust the
45
o
screw to increase the size of the peak. Remember to switch back into line mode
