This week's How-To Tuesday is a two parter; this week we show how to convert that old digital camera you're got in your closet to one that takes a picture automatically every second until the memory card is full, which will we use in next week's How-To, where we'll put that camera on a kite. There are many other applications once you hack a digital camera to take a shot a second, and we'll also go over those in future How-Tos, for example: mounting to a car, bicycle, city bus, house pet, cubicle, and other fun things.
A couple years ago we bought an Olympus "Camedia" D-360L 1.3 Megapixel digital camera which took "okay" pictures
and used that goofy SmartMedia format. At the time it was a good camera, but eventually we moved on and it's been
sitting in the basement waiting for a project, dreaming of the day it'll fly, fly away like a bird.
There's been a lot of interest in taking digital photos from kites over the last few years, but all the articles we've seen involve really complicated gear and remote controls, most being very expensive—all we want to do is take as many photos as we possibly can until the battery dies or the card is full. Most importantly, we wanted to do this on the cheap since there's a good chance the camera will get smashed. We checked eBay and places like Fry's Electronics and found a lot of crappy digital cameras that people will be able to use to take photos from kites. The project shouldn't cost more than $30 for the camera and the parts.
1 digital camera that will be hacked apart
RadioShack 1 LM555 Precision Timer - 8 Pin DIP
Wires, solder, hot glue
Many cameras will work with this hack, but we realize digital cameras are different—so this week we're going to show you the theory behind our digital camera automation, and next week we'll show you how to string it up to a kite. As we get feedback from the folks trying this at home, we'll add more ways to automate the digital camera hack.
Our soon to be airborne camera is an Olympus D-360L. A little bulky for kite pictures, but a good experimenter camera to get started.
Only 4 screws held the camera together, and quickly the camera face and back plate were off—this is another reason that old digital camera is good for hacks.
We located the shutter mechanism and popped the button off. Under the button there are 4 contacts, one was labeled "shutter" and that was the one we were after.
We then found positive and negative leads coming from the batteries (red and black). We're going to tap in to these and power our timer chip. To do this we simply soldered two wires directly from the leads.
We also soldered a wire directly to the lead that says "shutter" this is what triggers the camera when the black wire (negative) it applied to it. If you're testing your own camera this is a good way to test how the camera takes photos, once you figured that out, solder the wire from that button/lead.
For kicks we tested how many volts were going through, just to see what's flowing
through there (it was 5.98v) which makes sense since the camera takes four 1.5v AA batteries.
The Timer Chip
The LM555 Precision Timer (8 Pin DIP) is available for $1.49 or less at every RadioShack we've ever been in.
This chips allows us to simulate the button being pressed continually once we wire the power from the camera through it and then in to the shutter.
Once you get the chip, you can solder it up according to our diagram below or you can use a breadboard to test. A
available at RadioShack) will allow you to test wiring and the chip before you commit to soldering it all up.
With the chip pins down and the little round dot at the upper left, the numbers are 1 to 4 going down on the left side and 5 to 8 on the right side going up.
The black wire (negative) goes to the 3rd pin, Red (positive to the 4th pin). Run a wire from the 2nd to the 6th pin (or just fold the pins over the back and solder) then connect the 6th to the 7th pin. Last up, run the shutter wire to 6th pin. For the hardware geeks out there, you can of course add resistors and capacitors to change the timing (and possibly do a better job of not frying the camera than we did).
Once we tested the chip and the camera snapped dozens of photos without having to press a single button we then added the wires to the outside of the camera.
We used a small plug found in a pile of spare parts just so we could unplug it when not in use, or if we want to use for other projects. You don't need to do that, but we did for ease of use.
After that, we hot glued the chip as well as the wires to the outside of the camera.
The finished product. It works! So that's it for this week, next week we'll show you how to mount the hacked digital camera to a kite (and other things) to take photos automatically.
Phillip Torrone can be reached via his personal site: http://www.flashenabled.com