Camera Controller June 29

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UPDATE: New controller here

Early June, we do a trip up to Mendocino every year. It’s really dark up there, so sky/night photography is very cool to do up there. However, I’m really a morning person. Morning people and night photography don’t work well– especially on the pacific coast where you can have skyglow from ocean reflections well past midnight in the summer. Really cool night photography frequently requires hours long exposures. This one, is only about half an hour (apologies for the quality of the scan, high quality forthcoming):

Anyway, I picked up some parts I wanted to play with anyway:

The upper bit is an Arduino — it’s an ATMega168 AVR microcontroller, a USB interface, and some other cool bits. It’s designed to take “shield” boards, which plug into the top of it. It’s on 0.1″ pin spacing, so you can use perfboards to prototype things up.

The lower bit is the Bodhilabs switch-mode power supply. It takes 1.1V to 4.5V and steps that up to 5V. This module is set up to take two AA batteries (NiMH or Alkaline) and provide 5V to the Arduino. I’ve got another one that takes a single AAA and outputs 3.3V (more on that one later).

Here’s what I built with it (working prototype, all but one function rolling):

It’s a little ugly right now, but works! Basic functions listed:

  1. Triggers D70s via IR and my film camera via transistor.
  2. Three modes:
    1. “Trigger” - just triggers the cameras when you push the red button
    2. “Intervalometer” - Triggers the cameras every “n” seconds or minutes (range is 1 second to 6 minutes)
    3. “Long exposure” - Triggers the camera for a long exposure (range is 1 minute to 6 hours) (D70s only goes to 30m, but the film camera can go all 6 hours)
  3. The trimpot sets the time, it’s dual-scaled: 0-1:00 is half the range, 1:01-6:00 is the other half of the range. Basically, the difference between a 2m and a 4m exposure is a lot more important than the difference between a 2h05m and a 2h15m exposure.
  4. Currently not implemented is the Xbee-link. This becomes the red button, up to 300′ away (or more, I got 1000′ unreliably out of my Series 2.5 xbees). This is actually just using the GPIO capability of the Xbees, so the remote is entirely dumb– an xbee, a battery, and a switch.

Update! I uploaded the source code, it’s available here: http://photo.benpeoples.com/dist/arduino/sketch_080625a.zip

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