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6.5 Setting the focus recovery speed
Only attempt the following procedure after checking the error swing and minimising the effects of any
back reflections.
The objective pre-set values loaded during section 6.2 contain PID values. PID is a common control
loop mechanism that allows the PureFocus850 to maintain focus on the sample. The magnitude of
the proportional (P), integral (I) and derivative (D) gains define the rate at which the PureFocus850
recovers sample focus and focus stability.
Whilst the pre-set values will be approximately correct for a given sample type and objective, it likely
these values will need to be changed to achieve optimal performance.
For access to all PID settings, click on the PID submenu in the main PureFocus GUI.