02/24/13

DIY Water Balloon Photography Tutorial

One of the interesting techniques I hadn’t still tried until now was to capture an exploding water balloon just in the moment the plastic breaks, but the water still has the shape of a balloon. I didn’t want to invest any money in laser barriers or something similar, so I built a very simple mechanism that wouldn’t give me the perfect timing but maybe an acceptable approach.

Materials I used:

  • 2 sewing needles
  • A pice of plastic of about 20cm of length to build the lever.
  • 3 meter camera cable (for ease, depending on camera position)
  • A plastic washbowl
  • A small flash with wireless remote
  • A bag of small water balloons
  • A hot glue gun if possible (or just glue)
  • A tripod to hold the mechanism and water balloon, and another to hold the camera.
  • A mop!

Camera and flash settings:

  • Shutter of 1/100 or similar is enough, because we’ll illuminate the water balloon with the small flash only.
  • I recommend using an apperture of f/8 or narrower, because sometimes water goes in many directions and this way we’ll get more dof.
  • For the tests the flash was at 0.5m approx, at 1/64 of power. I recommend using the lowest power if possible to get a more sharp result.
  • Camera focus must be set to manual and I also recommend to adjust the frame for each photo since the size of the water balloons is not always the same.

Shutter trigger construction:

About the shutter trigger, my Canon 5D MKII uses an N3 connector, so I cut an old shutter cable to build the new one. It has three wires (Ground, Shutter, Focus) that will allow us to make a photo by doing a short circuit between Shutter and Ground wires. I’ve marked with a green dot the two necessary pins in the photo of the N3 connector. It’s not necessary to use the Focus wire since the camera will be in manual focus.

To build the other side of the wire, I welded each wire (Shutter, Ground) to a needle. Then I used the hot glue gun to attach the needles to a long piece of plastic with a little inclination so that if the needles touch a rigid surface they will touch each other. My initial idea was that the water of the balloon would short circuit the two wires, but at practice it didn’t result in my case, so with a little inclination in the needles they also touched each other when breaking the water balloon.

To hold the lever I used the materials I had at home, but it’s possible to hold it in many other (and better) ways.

Once the setup is mounted, a water balloon is hold with a string in front of the lever so that when the lever is released it will break the balloon and the needles will also touch each other to activate the camera shutter and make the photo, so the only thing we have to do is hold the lever in a higher position and release it to make each photo.

Photos of the parts and results:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Video of the mechanism in action:

As you can see the results are quite different between each other, because the timing was a little unpredictable. There are a lot of ways to improve this first test, trying to anticipate the explosion by placing the shutter cables in another place in the lever or changing the way the wires touch each other.

Opinions and questions welcomed ;)

02/13/13

Light Painting Wireframing tool

The idea:

Create a tool that projects a laser net to combine with the Light Painting photography technique, so that when projecting this net over a scene, it “seems” to be a wireframing view of a 3D modeled scene.

Solution:

Using only one laser pointer, create a set of horizontal and vertical lines that combined with the photo long exposure will result in a laser net. The laser pointer is moved by two RC servos controlled with a PWM signal generated by a 16F876A PIC microcontroller.
Once the circuit is done, the program can be configured to change laser speed, offset between lines and net size.

For the video I used a 7.4V LiPo battery, the voltage is regulated by a 7805, and the laser pointer uses one of the PIC 5V outputs with a 25 Ohms resistor.

Demonstration video with photo samples:

 

 

04/23/12

DIY LED torch for light painting: Results

I tried my recent built tool a few days ago, and I’m quite pleased with the results. Even using the LEDs at less than half power they illuminate a lot and worked great to create light orbs and other shapes like letters. Some examples below.

06/30/11

DIY Amazon Kindle 3 case

I purchased the new Amazon Kindle 3 some weeks ago, and I’m really satisfied with it, but I found the original cover too expensive, so I decided to do my own using a DVD case of a very bad movie instead.

The procedure:

    1. Take the worst DVD movie you find at home.
    2. Open the case completely so you separate and take out the paper with the synopsis and photo of the movie. You can flip this same paper as I did and put it inside again to get a white cover.
    3. Use a cutter to cut any plastic part of the inside of the cover that may annoy.
    4. A standard DVD case it’s slightly shorter than the Kindle so we’ll also cut the half top part of the case in order to close the cover without problems with the Kindle inside (see photos).
    5. Cover done!