Intro: High Speed Flash Photography
This is a picture of a screw driver mid bounce.
After reading about high speed photography in a magazine I was inspired to dig through my closet and see what I could come up with. I used a home made make-screen to trigger the flash while my digital camera was waiting with the shutter wide open.
It looks like I just stuck the screwdriver into the carpet, but I dropped it onto the makescreen. The second picture is of an airsoft pellet going through the makescreen.
Step 1: Tools and Materials
aluminum foil (Thinner the better)
airsoft gun (at least thats what I used)
The great thing about this project is the low costs involved. I went to a photo finishing place and asked if they would give me the leftovers and they happily gave me three.
I wanted the thinest aluminum foil available, so I picked up the foil and the wax paper at the dollar store.
Step 2: Carefully Disassemble the Camera
Peel off the stickers and use the screwdriver to gently open the tabs on the camera.
Once you get the back off, take the battery out.
WARNING: THE CAPACITOR IS STILL CHARGED UP AT THIS TIME, YOU MUST SHORT IT TO BE SAFE.
carefully pry out the film holder assembly. the flash circuit will come out with it.
Use an insulated screwdriver to short the capacitor by touching both leads with the blade of the tool. You know it worked when it sparks and pops at you. do it until it stops sparking. IF YOU DON'T DO THIS YOU RUN THE RISKS OF GETTING SHOCKED BY OVER 300 VOLTS.
Step 3: External Reset and Trigger
You can now remove the circuit board from the film cartridge by unhooking a small spring on above the lens assembly.
On the first camera that I modified I had to manually reset the flash after each shot. I wired up and external switch to make it easier by following the traces on the circuit board and soldering in a switch. The second camera I modified automatically recharged the flash, so a switch wasn't necessary.
To trigger the flash, you connect the two irregularly shaped metal attachments on the side of the board where the alligator clips are shown. Once you've gutted the electronics of the camera it's fun to test it by putting a battery in and shorting the two metal peices with a screw driver or bit of wire, just be very careful of the high voltages involved.
After this picture was taken, I soldered permanent wires to the trigger
Step 4: Making the Makescreens
A makescreen is nothing more than a really simple switch. Two pieces of foil and a sheet of wax paper is all you need.
I tried to find the thinest aluminum foil around by finding the cheapest. The wax paper shouldn't be the really thin kind found at deli's and butcher shops, but the kind you can actually see the sheen of the wax on the paper.
1) Rip two sheets of aluminum foil I used about eight or nine inches off the roll.
2) Rip off a piece of wax paper thats longer than the lauminum foil. I used about ten inches.
3) Layer the wax paper between the foil stagering the layers so that none of the foil touches. I left a good 1/4" to 1/2" border.
4) Using a clothes iron on high with no steam gently iron the sandwich together. It only takes a few seconds.
5) Sit back and admire the completed makescreen.
Step 5: Putting It All Together
To use the makescreen you use the aligator clips to attach one sheet of foil to one of the oddly shaped metal bits (sorry about the technical jargon) in the camera and the other piece of foil to the other oddly shapped metal bit. This will be easy if you've already soldered leads with alligator clips on them. Make sure you don't let the aligator clips touch both peices of foil or the system won't work.
I used my Kodak Digital Camera. It's certainly not the latest greatest camera on the market as I've had it for a few years now. I put the camera into manual mode and adjusted the shutter time to 1 second. I charged the flash, pressed the camera shutter button and droped the screwdriver on the make screen sitting on carpet. I wish I could say that I got a great picture on the first try but it took some practice to get the timing right.
I was able to reuse the makescreens several times before they were permanently shorted.
The room has to be fairly dark inorder for the picture to come out right. This shot was taken under my desk with the blinds closed and the lights off.
Step 6: Ballistic Setup
I taped the makescreen to a cardboard box and shot at it with my airsoft gun. this photograph shows the plastic pellet hitting the screen. According to the airsoft manufacturer, the pellet is moving at over 100 ft/second.