Commands and Sequences

LA⁴ accepts lighting instructions as a sequence of CSV rows written to ~/la4_sequence.csv on the node. Each row is a command: the register name followed by its parameters, comma-separated.

Load and execute a sequence using the boardio program in the device with the following commands:

• boardiocli uSeq — loads the sequence file into the firmware
• boardiocli runSeq — starts execution

All commands return BOARDIO_READY on success or BOARDIO_ERROR on failure which are sent over your listener as message events.

Command reference

MODEL_LIGHT

Controls the constant model light (continuous, non-flash illumination).

Parameter	Values	Min	Max
Power level	Percent %	0 (OFF)	100

Example — turn on the model light at 50% power:

MODEL_LIGHT,50

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ALL_4_NIKON

Shoots one picture with all four LED lights. Use with Nikon and Sony cameras.

Parameter	Values	Min	Max
Power level	Percent %	0	100

Example — fire all four LEDs at 80% power:

ALL_4_NIKON,80

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ALL_4_CANON

Shoots one picture with all four LED lights. Use with Canon cameras and when using other camera manufacturers (e.g. Fujifilm, Panasonic).

Parameter	Values	Min	Max
Power level	Percent %	0 (OFF)	100
Shutter speed	Milliseconds	0 (OFF)	109

Example — fire all four LEDs at 80% power with a 105 ms on-duration:

ALL_4_CANON,80,105

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OLAT_4_NIKON

Shoots four pictures, one per LED, firing each in sequence. Use with Nikon and Sony cameras.

Parameter	Values	Min	Max
Power level	Percent %	0	100
Drive Mode	0 = Single Frame, 1 = Continuous (use with all continuous modes: High+, High, Mid, etc.)	-	-

Example — shoot one-light-at-a-time at 75% power in continuous mode:

OLAT_4_NIKON,75,1

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OLAT_4_CANON

Shoots four pictures, one per LED, firing each in sequence. Use with Canon cameras and when using other camera manufacturers (e.g. Fujifilm, Panasonic).

Parameter	Values	Min	Max
Power level	Percent %	0 (OFF)	100
Drive Mode	0 = Single Frame, 1 = Continuous (use with all continuous modes: High+, High, Mid, etc.)	-	-
Shutter speed	Milliseconds	0 (OFF)	109

Example — shoot one-light-at-a-time at 75% power in continuous mode with a 105 ms on-duration:

OLAT_4_CANON,75,1,105

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N_LIGHTS_NIKON

Shoots one picture with a chosen subset of the four LEDs. Use with Nikon and Sony cameras.

Parameter	Values	Min	Max
Power level	Percent %	0	100
LED1	0 = OFF, 1 = ON	-	-
LED2	0 = OFF, 1 = ON	-	-
LED3	0 = OFF, 1 = ON	-	-
LED4	0 = OFF, 1 = ON	-	-

Example — fire LEDs 1 and 3 at 60% power (LEDs 2 and 4 OFF):

N_LIGHTS_NIKON,60,1,0,1,0

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N_LIGHTS_CANON

Shoots one picture with a chosen subset of the four LEDs. Use with Canon cameras and when using other camera manufacturers (e.g. Fujifilm, Panasonic).

Parameter	Values	Min	Max
Power level	Percent %	0	100
LED1	0 = OFF, 1 = ON	-	-
LED2	0 = OFF, 1 = ON	-	-
LED3	0 = OFF, 1 = ON	-	-
LED4	0 = OFF, 1 = ON	-	-
Shutter speed	Milliseconds	0 (OFF)	109

Example — fire LEDs 1 and 3 at 60% power with a 105 ms on-duration:

N_LIGHTS_CANON,60,1,0,1,0,105

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SHOOT_BLANK

Performs a single DSLR shot with no lights. The duration controls how long the shoot pin is physically pressed.

Different cameras require different durations to reliably actuate the shutter:

• Normal range: 20–50 ms
• Fast-shooting cameras: 5–10 ms
• Slow-shooting cameras: 50–200 ms

If the duration is too short the camera will not trigger. If it is too long the camera may fire two shots instead of one.

Parameter	Min	Max
Duration	0	1000

Example — trigger a single shot with the shoot pin held for 30 ms (normal-range camera):

SHOOT_BLANK,30

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LED_FAN

Controls the LED cooling fans.

Parameter	Values
Enable	0 = OFF, 1 = ON

Example — turn the fans on:

LED_FAN,1

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DIGITAL_POLARIZER

Enables or disables the digital polarizer.

Parameter	Values
Enable	0 = OFF, 1 = ON

Example — enable the polarizer:

DIGITAL_POLARIZER,1

Sony Cameras

Sony cameras use the same firmware commands as Nikon. Use ALL_4_NIKON, OLAT_4_NIKON, and N_LIGHTS_NIKON for Sony.

Example sequence CSV file

MODEL_LIGHT,30
LED_FAN,1
ALL_4_CANON,80,105

This sequence does three things in order:

1. MODEL_LIGHT,30 — turns on the constant model light at 30% power, providing continuous illumination for framing.
2. LED_FAN,1 — turns on the cooling fans before the flash LEDs fire.
3. ALL_4_CANON,80,105 — fires all four LEDs simultaneously at 80% power with a 105 ms on-duration, triggering one shot on a Canon camera.

Sending a sequence to LA⁴. Example cross-polarization

The sequence file is written and executed by sending a cmd request to the pycom networking software running on the device. You need to compose a shell command to write the CSV content to ~/la4_sequence.csv, then call boardiocli uSeq to load it and boardiocli runSeq to run it.

The example below captures two shots with a Nikon camera: one without the digital polarizer and one with it. This is a common cross-polarization technique — the first shot captures both diffuse and specular light, the second suppresses specular reflections, leaving only diffuse.

{
    "type_": "cmd",
    "command": "echo \"DIGITAL_POLARIZER,0\\nALL_4_NIKON,10\\nDIGITAL_POLARIZER,1\\nALL_4_NIKON,1\" > /home/rigsters/la4_sequence.csv && boardiocli uSeq && boardiocli runSeq",
    "id": "31548ca2",
    "name": "My PC App",
    "ip": "192.168.0.100",
    "port": 5000,
    "version": "0.1.0",
    "coordinator": true
}

The sequence file this writes to the node:

DIGITAL_POLARIZER,0
ALL_4_NIKON,10
DIGITAL_POLARIZER,1
ALL_4_NIKON,1

1. DIGITAL_POLARIZER,0 — disables the polarizer so the first shot captures both diffuse and specular light.
2. ALL_4_NIKON,10 — fires all four LEDs at 10% power and triggers one shot.
3. DIGITAL_POLARIZER,1 — enables the polarizer to suppress specular reflections.
4. ALL_4_NIKON,1 — fires all four LEDs at minimum power and triggers a second shot, now capturing only diffuse light.