A cable release is a device used to remotely control the camera’s shutter. Its one end connects to a camera through the cable release port, while the other end has a button or a switch that can keep the shutter open for as long as it is ‘pressed’. It is used primarily to take advantage of what is called the bulb setting. Under this setting, exposures ranging from a few minutes to a few hours is now possible. With this accessory, pictures may be taken without touching the camera’s body, thus, shaking caused by pressing the shutter could be completely eliminated.

This article explains how you can build one (for Canon DSLRs) that performs technically the same function, equally as reliable, but costs just a fraction of the commercially available counterpart (and the best part is, you actually built it yourself!).

WARNING: I will not be responsible for any damage caused to your equipment. Follow instructions at your own risk!

DIY Cable Release

For this do-it-yourself (DIY) project, you only need (1) a length of cable with 2 wires, (2) a 2.5 mm earphone jack, and (3) any type of switch. You will also need a pair of scissors, some electrical tape, and a soldering iron (optional). All components cost less than 50 php (approx  $1), and may be assembled in less than an hour.

Materials needed for the DIY cable release  (switch, wires, and plug)

Get the materials ready. Basically what you need to do is to connect the switch on one end,  and the earphone jack on the other end. You may use a pair of scissors to expose the copper wires/leads.

The switch will be connected on one end, while the earphone jack will be connected on the other end.

Connect one end of the wire to switch as shown in the picture. The cable has two leads (or wires). The switch should be able to ‘short’ the two wires when the switch is turned on (or the circuit is closed). The purpose of the switch is to momentarily create a ‘bridge’ or a ‘connection’ between the two wires. Once a connection is made, the camera senses it and immediately opens the shutter. Thus, any type of switch may be used for this purpose. Set the switch to ‘off’ position (circuit is open) before making the connection.

This image illustrates how to connect the switch to the 2 wires.

Connect the other end of the wire to the earphone jack as shown in the picture.  Again, the cable has two leads (or wires). The earphone jack has 3 connection points. We are only interested in the “center (core) pin” and the “outer pin”. One of the wires must be connected to the center pin, while the other wire must be connected to the outer pin. Note that one of the pins (the one that is between the “center pin” and the “outer pin”) is left intentionally unconnected as it will be used for future improvement of the DIY cable release (will not be discussed yet in this DIY project, stay tuned for new DIY posts).

This image illustrates how to connect the pins of the earphone jack to the 2 wires.

Use electrical tape to insulate all electrical connections.

Cover all electrical connections.

Locate the cable release port of your camera. In this particular model (Canon 450D), the port is located between the ‘video out’ port and the ‘USB’ port (consult the manual).

In a Canon 450D, the cable release port is located between the ‘video out’ port and the ‘USB’ port.

Connect the cable release to the camera through the cable release port.

DIY cable release is now connected to the camera.

Set the camera to manual mode and activate the ‘bulb’ setting (consult you manual on how it is done). Test the DIY cable release by turning the switch on (circuit is closed). If successful, the camera should readily respond. It will raise the shutter (keep it open) for as long as the switch is set to “on” position.

The time shown on the LCD display (in this case 1’39 or 1 minute and 39 seconds) indicates the length of time the exposure is left open in a single shot.

Enjoy the DIY cable release and happy shooting!

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© Anthony Urbano (Manila, Philippines)