Camtroller 

 Modular camera trigger, just add 5V.

Problem:  There are moments when you need to monitor an area for an unknown period of time in order to capture a particular event.  I am, of course, speaking of family portraits in that rare moment when the entire group is smiling, with their eyes open.  Ok, I jest.  This problem is focused primarily on changes in motion--for practical and non-practical purposes.  If you have ever seen blurry surveillance where the perpetrator committed some misdeed and got off clean due to the low resolution of the video footage, you understand that a clearer image makes all the difference.

Solution:  This is a simple solution, depending upon the camera in question.  The camera must accept a wired remote that operates the focus and shutter only.  I decided to expand the functionality of the controller by making it modular.  In this fashion, it can serve as the trigger for any device that outputs five volts.  A motion detector with a transformer (five volt wall-wart), the PanCam, an accelerometer or even DARN can all be utilized.  If using this as a surveillance camera, there are camera hacks to automatically upload the photo to Flickr.  Of course if motion is the only criteria, I encourage you to explore other options. 

This project is as simple as a microcontroller project gets.  Wait for a signal then focus the camera and click the shutter after an appropriate interval. 

That's all there is to the schematic.  One input, two outputs to relays.  The microcontroller can source 20mA per pin.  Couple this with low current relays and there is no need for additional hardware (opto-couplers or transistors.)  And here it is in the physical world:

The plain black Bic shown above is there just to provide scale.  Note the lack of clock signal.  Since timing was less than critical, the internal oscillator was used to preserve space (and subsequently parts.)  The software is almost as easy as the hardware in Picbasic Pro:

ADCON1 = %00001111
TRISB = %00000100
PORTB = 0
MAIN:

pause 250
stay: if PORTB.2 = 0 Then stay
PORTB.1 = 1
PAUSE 1000
PORTB.0 = 1
PAUSE 500
PORTB.1 = 0
PORTB.0 = 0
PAUSE 1000
Pause 1000
goto Main

END

Cake and pie coding.  The timing is for a Canon Rebel (from a photographing fiend.)  It has been used somewhat successfully for capturing backside portraits from unsuspecting passersby while using the motion detector for the trigger.