Exposure Loops

Within an exposure loop, the interaction of the Exposure, Clear, and Shutter Open modes determines how the camera behaves during a sequence. On this page, the sample command sequences show how each exposure mode acts in combination with each Clear and Shutter open mode. Not all supported cameras have programmable shutter control, remember to check for availability of a particular mode.

Key	Description
ClearN	Clear sensor N times as specified in clear_cycles
OS	Open shutter and perform PARAM_SHTR_OPEN_DELAY
CS	Close shutter and perform PARAM_SHTR_CLOSE_DELAY
EXP	Expose sensor for exposure_time
I->S	Transfer image array to storage array (frame transfer)
Readout	Readout sensor (readout storage array for frame transfer)
WaitT	Wait until trigger
EXP until notT	Expose sensor until trigger end (BULB_MODE)

Items in ITALICS repeat M times for a sequence of M exposures.
Items in BOLD are outside of the sequence loop.

TIMED_MODE command sequences:

Clear Mode	Shutter Mode	Command Sequence
CLEAR_PRE_EXPOSURE	OPEN_PRE_EXPOSURE	ClearN, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, ClearN, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	ClearN, OS, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	ClearN, EXP, I->S, Readout
	OPEN_NEVER	CS, ClearN, EXP, I->S, Readout
CLEAR_PRE_SEQUENCE	OPEN_PRE_EXPOSURE	ClearN, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, ClearN, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	ClearN, OS, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	ClearN, EXP, I->S, Readout
	OPEN_NEVER	CS, ClearN, EXP, I->S, Readout
CLEAR_NEVER	OPEN_PRE_EXPOSURE	OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	OS, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	EXP, I->S, Readout
	OPEN_NEVER	CS, EXP, I->S, Readout

TRIGGER_FIRST_MODE command sequences:

Clear Mode	Shutter Mode	Command Sequence
CLEAR_PRE_EXPOSURE	OPEN_PRE_EXPOSURE	EXP+WaitT, ClearN, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, EXP+WaitT, ClearN, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	EXP+WaitT, OS, ClearN, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	EXP+WaitT, ClearN, EXP, I->S, Readout
	OPEN_NEVER	CS, EXP+WaitT, ClearN, EXP, I->S, Readout
CLEAR_PRE_SEQUENCE	OPEN_PRE_EXPOSURE	Clear+WaitT, ClearN, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, Clear+WaitT, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	Clear+WaitT, OS, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	Clear+WaitT, EXP, I->S, Readout
	OPEN_NEVER	CS, Clear+WaitT, EXP, I->S, Readout
CLEAR_NEVER	OPEN_PRE_EXPOSURE	EXP+WaitT, ClearN, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, EXP+WaitT, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	EXP+WaitT, OS, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	EXP+WaitT, EXP, I->S, Readout
	OPEN_NEVER	CS, EXP+WaitT, EXP, I->S, Readout

STROBED_MODE command sequences:

Clear Mode	Shutter Mode	Command Sequence
CLEAR_PRE_EXPOSURE	OPEN_PRE_EXPOSURE	Clear+WaitT, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS,Clear+WaitT, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	OS, Clear+WaitT, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	Clear+WaitT, EXP, I->S, Readout
	OPEN_NEVER	CS, Clear+WaitT, EXP, I->S, Readout
CLEAR_PRE_SEQUENCE	OPEN_PRE_EXPOSURE	ClearN,EXP+WaitT, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, ClearN, EXP+WaitT, EXP, I->S, Readout,CS
	OPEN_PRE_TRIGGER	ClearN, OS, EXP+WaitT, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	ClearN, EXP+WaitT, EXP, I->S, Readout
	OPEN_NEVER	CS, ClearN, EXP+WaitT, EXP, I->S, Readout
CLEAR_NEVER	OPEN_PRE_EXPOSURE	EXP+WaitT, OS, EXP, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, EXP+WaitT, EXP, I->S, Readout, CS
	OPEN_PRE_TRIGGER	OS, EXP+WaitT, EXP, CS, I->S, Readout
	OPEN_NO_CHANGE	EXP+WaitT, EXP, I->S, Readout
	OPEN_NEVER	CS, EXP+WaitT, EXP, I->S, Readout

BULB_MODE command sequences:

Clear Mode	Shutter Mode	Command Sequence
CLEAR_PRE_EXPOSURE	OPEN_PRE_EXPOSURE	Clear+WaitT, OS, EXP Until notT, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, Clear+WaitT, EXP Until notT, I->S, Readout, CS
	OPEN_PRE_TRIGGER	OS, Clear+WaitT, EXP Until notT, CS, I->S, Readout
	OPEN_NO_CHANGE	Clear+WaitT, EXP Until notT, I->S, Readout
	OPEN_NEVER	CS, Clear+WaitT, EXP Until notT, I->S, Readout
CLEAR_PRE_SEQUENCE	OPEN_PRE_EXPOSURE	ClearN, EXP+WaitT, OS, EXP Until notT, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, ClearN, EXP+WaitT, EXP Until notT, I->S, Readout, CS
	OPEN_PRE_TRIGGER	ClearN, OS, EXP+WaitT, EXP Until notT, CS, I->S, Readout
	OPEN_NO_CHANGE	ClearN, EXP+WaitT, EXP Until notT, I->S, Readout
	OPEN_NEVER	CS, ClearN, EXP+WaitT, EXP Until notT, I->S, Readout
CLEAR_NEVER	OPEN_PRE_EXPOSURE	EXP+WaitT, OS, EXP Until notT, CS, I->S, Readout
	OPEN_PRE_SEQUENCE	OS, EXP+WaitT, EXP Until notT, I->S, Readout, CS
	OPEN_PRE_TRIGGER	OS, EXP+WaitT, EXP Until notT, CS, I->S, Readout
	OPEN_NO_CHANGE	EXP+WaitT, EXP Until notT, I->S, Readout
	OPEN_NEVER	CS, EXP+WaitT, EXP Until notT, I->S, Readout