So, everything is ready to run and you find that the battery is low on your DSLR and you didn't bring a spare. What's to do? Wouldn't it be nice to power your DSLR from a DC supply (auto or battery) and not worry about your battery running out in the middle of a set series of shots? Well, here is a small board you can make to eliminate the battery with a suitable battery replacement part. In addition it allows you to control the shutter from a serial port on your computer using many software applications.
While simpler versions exist, I like to use opto-couplers where I can just to keep things apart. While the camera's ground and the mount's ground will end up together at least we can keep the shutter circuitry on it's own.
Parts List
- 1 x LM317 linear voltage regulator
- 2 x 1N4001 diodes
- 1 x 220R 1/4W resistor
- 1 x 1K2 1/4W resistor
- 1 x 330R 1/4W resisotor
- 1 x 47K 1/4W resistor
- 1 x .01uF capacitor (ceramic etc.)
- 1 x 470uF 16v capacitor
- 1 x TO220 heatsink
- 1 x 2N3904 NPN transistor
- 1 x PC827 dual opto-isolator (or equivalent)
- 1 sheet of copperclad
- Some wire, solder etc.
And drawings of the board and layout:
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If you are using a serial port and have problems, try connecting pins 4 and 6 on the connector. The signal comes from pin 7 and ground from pin 5.
For a Photoshop document with layers of the board layout with a printable copper layer click here
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