ScanImage requires an initialization (INI) file, usually named standard.ini, to be selected at startup. This file specifies & initializes all the state variables for the ScanImage configuration and determines which variables are associated with configuration (CFG) and user (USR) files. Typically there is only one INI file per ScanImage installation (a 'rig'). A subset of 'Rig Specific' variables are demarcated in the INI file. These variables are not associated with either CFG or USR files and are not modified during ScanImage program operation. T
ScanImage r3.5 introduces some changes to the way INI files are handled. In addition, the frequently-modified variable section of the model INI file has been modified (simplified).
Changes in INI File Handling
Rig Configuration Variables
The INI file contains a large number of variables. Only a small number of these typically require adjustment for a ScanImage installation to a new rig. These Rig Configuration variables are clearly grouped at the beginning of the standard_model.ini file. Users should adjust these values to match
The INI file parser is whitespace sensitive. The format <VARNAME>=<VARVALUE> must be strictly followed, i.e. no space to left or right of the equal sign
ScanImage r3.5 has added a few and removed several variables from this frequently-modified section. [
View Frequently Modified Section of Standard.INI File
]
New and notable INI file variables in this section are:
triggerLineIndex: (Previously below rig-specific section) Allows specification of the static digital output line used as shared trigger source for acquisition, mirror, and Pockels cell board(s). The use of Port 0 on the board specified by triggerBoardIndex is assumed.
triggerInputTerminal: Specifies the single Programmable Function Interface (PFI) terminal which the acquisition, mirror, and Pockels Cell board(s) will all use as their default trigger input. This terminal on the one or more boards should be connected to the trigger source specified by triggerBoardIndex and triggerLineIndex. This is part of trigger simplification feature in r3.5.
externalTriggerInputTerminal: Specifies the single Programmable Function Interface (PFI) terminal which the acquisition, mirror, and Pockels Cell board(s) can all use as their optional external trigger input, as described in External Triggering.
externalTriggerTimeout: Specifies time to wait for external trigger input to arrive. See External Triggering.
outputBoardClockTerminal: Specify terminal, either PFI or RTSI(0-6), which will be used to synchronize the clocks of the acquisition/mirror board to the Pockels cell board (if present). Previously RTSI7 was assumed/required. See Clock Synchronization for more details.
maxBufferedGrabTime: Specifies max duration, in seconds, of an acquisition (effectively limiting the max number of frames) to allow without using 'SaveDuringAcquisition' option. This value should typically not be altered. Longer acquisitions should employ the new [Continuous Disk Logging] feature.
maxFlybackRate: This value is reserved for r3.6.
scanOffsetX/Y: (Previously below rig-specific section) Specify offset voltages for mirror command signals. These variables are unique among the Rig Specific variables in that they can be altered during ScanImage operation. See [Beam and Scan Alignment Tools] for more information.
parkAmplitudeX/Y: (Previously below rig-specific section) Specify voltages for X/Y mirror when parked. 
Beam safety should be considered in setting these values.
maxAmplitudeX/Y: Specify max voltage allowed for X/Y amplitudes. This clamps the sum of the scan amplitude and the scan shift set in ScanImage, for each dimension.
Shutter Variables_
The separate values for 'open' and 'closed' have been removed. Variables open and epiShutterOpen are sufficient to specify 'polarity' of shutter interface.
shutterBoardIndex: See Shutter output line(s) can be on any board.
Motor Variables
The number of variables in the rig-specific motor section has been greatly reduced. Two variables, firmware and posnResolution, are new in r3.5. See MP-285 Interface Improvements for details.