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Picture of the Month – May 2009

Saturday, June 6th, 2009

I’m a little late posting my picture of the month for May – but better late than never.

Picture of the Month - May 2009

Picture of the Month - May 2009

Given that I spent quite a bit of May experimenting with High Speed Flash Photography, it’s only right that my picture of the month should reflect that.

So with that in mind, I picked this picture to represent a number of attempts to freeze a moment in time.

I’m using my homebuilt sound detector (described here) to trigger a flash in a darkened room. The sound that triggers everything is the pellet gun (shown here), firing a pellet at around 400 feet/second directly into the water balloon.

In order to get as crisp a picture as possible, I’m using a Vivitar 283 flash on its shortest duration of 1/30,000 second – keeping the shutter on my camera open for a couple of seconds as I fire the pellet gun.

To see pictures of the month from previous months, click here.

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The Tomato and the Pellet

Tuesday, June 2nd, 2009
Plum Tomato

Plum Tomato

When I first starting talking about shooting a ripe plum tomato with a pellet gun at close range, my wife had visions of tomato sauce splattered on every wall.

The tomato proved to be beefier and more resiliant than expected, however, with very little in the way of an explosion of color that I was seeking. As you can see in this photo, the pellet has passed through the tomato, leaving very little in the way of a visible path of destruction.

To get the solid black background, I’m using a glossy black ceramic tile, with a black fabric behind the tomato, draped over a foam board. As in previous sessions, I’m using a Vivitar 283 flash on its shortest duration (1/30,000 second) triggered by a sound detector in order to capture the moment of impact.

I digress, however – back to the tomatoes. Not satisfied by my results, I decided to try again, placing the pellet gun just inches away from the tomato.

Plum Tomato Shot at Close Range

Plum Tomato Shot at Close Range

As you can see in this picture, there is a more dramatic impact captured, although much of this is just the CO2 released by the pellet gun. You can also see that this tomato has survived multiple puncture wounds and is on its last legs.

I’m still searching for subjects that will make a good photograph. I had high hopes for the red tomato, reflected off the glossy black tile, but the impact was not as strong as I’d like. If you have any candidates you’d like to see explored, let me know.

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The Quest Continues…

Thursday, May 21st, 2009

…for the perfect water balloon explosion.  And while not perfect, I think today I’ve come about as close as I can with the basic equipment and setup I have at my disposal.

Balloon & Pellet

Balloon & Pellet

Now that I’ve got the basic timing down, I was able to capture the picture at the left, with the pellet (fired from a pellet gun at about 400 feet/second) in the picture and about to hit the water-filled balloon.

Because the difference between a hanging balloon, a balloon that has deflated with the water still hanging, and a complete watery mess are milliseconds apart, my timing consists of moving the sound detector by a matter of inches.

Pellet Inside Balloon

Pellet Inside Balloon

In this next picture, the pellet has literally just entered the balloon on the right, but the balloon has not deflated yet.

Again, the difference between these two pictures is so short that it’s hard to imagine. So all that’s left is to capture the instance after the actual point of impact when the balloon has collapsed, but the water still retains its shape as gravity starts to pull it down.

I couldn’t decide which picture I thought represented that best, so here’s a series of water balloons punctured by shots fired from a pellet gun.

And finally, the setup.  Last week, I had a comment on one of my water balloon pictures, asking that I show the setup I use in taking these pictures. So here it is.

Water Balloon Setup

Water Balloon Setup

Not the most elegant of setups, essentially you can see the camera (Canon 20D) on a tripod to the left, with the Vivitar 283 flash just to the right and below it.

I have the balloon hanging from a shoe lace that’s dropped from a ceiling brace, with a matte black backdrop behind the balloon. I’m using a roasting pan to capture the water as it falls from the balloon, with an inverted funnel to (hopefully) lessen the impact of the water falling.

On the table is a plastic tablecloth, with my sound detector device (described here) on the front left corner. For the actual shot, I move the sound detector to get the delay I want. On the far edge of the table is the homemade backstop for the pellets (essentially a cardboard box stuffed with 2 pieces of 1/4″ plywood, magazines, and newspapers).

And finally, on the front edge of the table are the pellet gun (described here) and safety glasses.

When I take the picture, I set the camera on a 1 second shutter speed, manually focused, with as large an aperture as possible. I turn off the lights, using a small flashlight to provide a limited amount of light. I then take aim on the balloon, use a shutter release to trip the camera shutter, and fire the pellet gun.

If it all works to plan, the sound of the gun triggers the flash just as the pellet reaches the balloon. And since the flash has a duration of 1/30,000 second, the camera sensor just captures that instant in time when the flash exposes the scene.

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