Capture a video by triggering the camera

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There are many ways to trigger the camera, depending on your physical layout and the precision required:

External trigger connector

The external trigger connector (marked I/O) accepts a 2.5mm wired remote shutter release cable or a daisychain genlock cable. The tip is trigger and the sleeve is ground. Any high quality Canon compatible remote trigger should work.

Trigger remotes

Examples of compatible trigger remotes that we have tested include:

  • Canon RS-60E3
  • Vello RS-C1II
  • Pixel RS-201

NOTE! : These remote cables have a feature that allows the button to be locked down. In your excitement it is easy to activate the lock, leaving the button depressed when you think it is released. If you activate the button lock down, then the camera will not operate as expected.

Wireless trigger remote

Low cost trigger


I quickly tested one Canon compatible wireless trigger as a customer was asking for a recommendation. I picked the wireless trigger based on my previous experience that a unit that uses standard AAA batteries is easier to keep running. I also bought a mix of tripod mount screws so I could attach the receiver to the edgertronic camera.

As expected, the wireless remote worked fine. I setup the camera outside and walked down the block. I was able to trigger around 60 meters from the camera, not testing any larger distance. All of this was very simple testing, not any kind of reliability or suitability testing.

What I liked about the Pixel 2.4GHz Digital Wireless Remote:

  • Easy to mount the remote to the camera (if you buy the extra screws listed above)
  • Uses standard batteries
  • Receiver blinks to indicate it is turned on
  • Both transmitter and receiver provide visual feedback that a trigger occured
  • Nice form factor, easy to hold transmitter in your hand
  • Supports multiple codes so you can use several in close proximity without causing false triggers

What could be better:

  • The slide switch on the transmitter, which allows selecting between single trigger, multi-trigger, and delayed trigger, is very flimsy. I would likely take a hot glue gun and fix the slider to the single trigger setting.
  • Transmitter doesn't have an on/off switch. When put away, if anything is pressing against the button, the batteries will go dead.

Long range wireless trigger

We haven't tried these personally, but a customer has and liked the performance.

External switch trigger

An external switch trigger comes with the camera. The external switch trigger is very similar to the multi-function button, but with the ease of switch location. For example, when I was taking a high speed video while welding, I held the stick welder handle in one hand and the external switch trigger in the other.

Contact closure trigger

Any contact closure will do to trigger the camera via the external trigger jack. Many of our customers have semi-permanent installations with a pair of wires daisy chained to the cameras to trigger them all simultaneously with a contact closure.

Trigger timing

For software versions 1.0 through 1.3, there is a 5ms debounce built into the trigger input. In these releases, the delay from the trigger fall edge to the triggered frame is 5 ms plus one to three frames.

For software version 2.0 and above, the trigger frame is the frame that occurs coincident or immediately after the trigger input fall edge or trigger event. When triggered, the delay from the trigger input to the start of the next frame is recorded as the trigger_to_exposure_delay in the metadata file. It is the delay from the trigger signal, after the 5ms debounce delay if enabled, to the start of exposure of the first frame following the trigger. This way you can know the phase between the trigger and the stream of frames. The delay will always be less than 1/framerate.

For software versions 1.4 though 2.2.0 there was no debounce built into the trigger input.

For software versions 2.2.1 and above there is a user settable debounce setting. If debounce is on, a 5 ms debounce delay occurs between the falling trigger edge and when the camera processes the falling edge. With debounce off, there is no delay and the falling edge is processed immediately. Click on the wrench in the button box, select the Preferences tab, and turn trigger debounce on or off depending on your application.

When triggered, the delay from the trigger input to the start of the next frame is recorded as the trigger_to_exposure_delay in the metadata file. It is the delay from the trigger signal, after the 5ms debounce delay if enabled, to the start of exposure of the first frame following the trigger. The trigger_to_exposure_delay can be thought of as the phase between the trigger and the stream of frames. The delay will always be less than 1/framerate.

Daisychain genlock

If you have two or more cameras, you can configure the cameras to use genlock. Special cabling is required to interconnect the genlock source camera to the genlock receiver cameras. For the 2 camera case, you can use the genlock cable that is included with each camera purchase. Use the genlock cable to attach to the external trigger connector on each of the 2 cameras. You can also use an accessory product, the Genlock Adapter for longer cabling runs and/or supporting more than 2 genlocked cameras.

Console serial port

The external trigger connector can also be used in the SDK developer mode for the Linux serial console port.


Trigger signaling depends on the Genlock mode selected. You can read about it in Genlock Signaling

Event trigger

I have a TriggerTrap[1] I use with the edgertronic high speed camera. You can trigger based on an audio event, change in video, motion, time delay, and many other options. TriggerTrap is a cabling system that connects your smart phone to the camera. Sanstreak doesn't specifically support using Trigger Trap with an edgertronic camera, but I found it works great. I ordered the TriggerTrap MD3-E3 Mobile Dongle & E3 Remote Release Cable Kit for Canon. Unfortunately, TriggerTrap went out of business. Too bad, it was one of the best thought out camera trigger devices I have seen.

Canon compatible remote trigger

The edgertronic camera supports 2.5mm remote trigger devices that are compatible with Canon cameras. I found around 200 hits when I searched Amazon for Canon camera remote triggers. Of course we haven't tested all of them (okay, we haven't tested any of them), but the advantage of supports a standard like the Canon 2.5 mm remote trigger jack is generally they work fine.

Another quick search for long range wireless camera trigger turned up PocketWizard specs indicate up to 500 meters. Call PocketWizard to make sure you get the right remote camera trigger cable that is compatible with a Canon camera.

Genlock trigger

At this time you can not use an physical external trigger (or switch closure) when the cameras wired for genlock.

Multifunction button

You can simply power on a pre-configured camera and press the multi-function button to trigger the camera. The challenge is how to set the aperture and f/stop correctly. A typical use of the multi-function button would be to use a laptop or tablet for framing and proper focus and lighting, then while activating the experiment, use the multi-function button to trigger the camera.
More info at Multi-function button.

Multicast network trigger

The camera also supports being configured to trigger when a multicast packet is received over the network connection. This is a good solution if you need several camera to trigger at approximately the same time, but do not want to run wires between the cameras.
More info at Multicast Network Trigger

CAMAPI trigger()

The Software Developer's Kit for the edgertronic camera, called CAMAPI, supports the trigger() API. CAMAPI is exposed over the network connection and the camera ships with host examples (written in python). You can easily access it via a web browser too:

replacing with your camera's IP address as necessary.

Each time to refresh your browser when pointing to that URL, the camera will trigger.

You can use the full CAMAPI for complete camera control.

If you need to trigger your camera from a long distance, you can wireless Ethernet extenders or high quality WiFi access points. Then you can wireless trigger the camera using the built in Web UI.

[1]Triggertrap company went out of business in January 2017.