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Two new articles posted: Using a 10-turn pot with a delay unit

and Selecting a flash unit for high-speed photography


Crossed-Beam Photogate Breadboard Kit, unassembled



The breadboard version of our crossed-beam photogate kit has been discontinued. For the project box version, click here.

The crossed-beam photogate uses a pair of infrared photogates oriented at right angles to each other. This type of photogate can be used to automatically actuate a camera shutter when an object passes through the beam intersection. This makes it useful for photographing birds and insects. If a camera is centered and focused at the beam crossing, the shutter will be actuated only when the object moves through the point of focus.


There are three parts to a crossed-beam photogate system:

Bird passing through crossed-beam photogate

Click here or on the photo to enlarge and show the photogate circuit.

Electronics: We provide a kit (CBP-O) for the detection and triggering circuitry. A breadboard and all electronic components and hookup wire are included. Assembly is required.


Photogate framework: We provide a kit (CBP-F) with pre-cut and pre-drilled sections of tubing so that you can quickly assemble a framework and align the photogates. The assembled gate shown above is 10" square (inner dimension), large enough for insects and small birds. You don't need this kit if you're planning to make a framework of your own design.


Shutter cord: You'll need a cord to connect the output of the trigger circuit to your camera shutter. We have a variety of cords available.


Online tutorials--both video and text/image--are available to help in building and using the crossed-beam photogate. You may wish to view the instructions before purchasing in order to see what's involved.


While triggering a camera is the most common application for the crossed-beam photogate, the circuit can also trigger low-voltage (<80 V) flash units and wireless transceivers and can be connected to the external input of a Multi-Trigger in order to use the delay timer.

Camera shutter cables

Select the shutter cable for your camera below. See the list of compatible cameras here.

Canon 80N3 cable with adapter Nikon MC30 cable with adapter Nikon MCDC2 cable with adapter
Canon 80N3 Nikon MC30 Nikon MCDC2
Canon 60E3 cable 3.5mm male-female extension cable 3.5mm connectors
Canon 60E3 3.5mm male-female extension Cable connectors (DIY)
  • The Canon 80N3 and the Nikon cables are about 1-foot long and may be coiled or straight, depending on what we can get from our suppliers. The stereo plug is 2.5mm, and a 2.5mm to 3.5mm stereo adapter is included for connection to a trigger box. A 6-foot extension cable may be purchased for just $1.95 more.
  • The Canon 60E3 cable is 6 feet long with 2.5mm and 3.5mm plugs.
  • DIY option: If you want to use a shutter release cable that you already own rather than buying one of ours, you can just get the 3.5mm male and female stereo connectors and follow these instructions.

Shutter cable option


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