13 September 2008
More High Speed Photography
Basically the way that I am able to freeze such high speed action is by using a special electronic flash that puts out an incredibly short burst of light (between 1/15,000 to 1/50,000 of a sec.). This brief pulse of light is what freezes the subject. Most commercially available flash systems produce a seemingly fast 1/1,000sec burst of light but that is not nearly fast enough for what I am interested in doing. Early on I learned that if I dialed these normal flash units down to 1/16th power I could achieve flash bursts on the order of 1/15,000sec. I did this for awhile and was able to do some interesting work. The problem was when you turn a flash down to 1/16th power you cut the light output dramatically. This can be overcome however, by moving the lights in closer to the subject, but this can be a problem with larger or skittish subjects.
The answer I determined was to find a dedicated high-speed flash system. The only system like this that I had ever heard of was made many years ago by a man named Ken Olson and is no longer in production. Used units were and still are impossible to find. I had also heard that these units could be dangerous to use because of the high voltage involved (as much as 3,500 volts was being passed through the cables connecting the capacitors to the flashheads) If you had a short in the system or a frayed cable this was certainly enough voltage to knock you on your rearend, and would very likely, be lethal. So I gave up for a while and made due with what I had. Then a few years later while doing an Internet search I came across a company called Fotronix which was making exactly what I was looking for. I called and spoke with Roy Dunn the owner of the company and he informed me that unfortunately there was not enough interest in the product (this is pretty specialized stuff) to continue production. I was in luck however because, he had one set left, a four flash head unit. I of course, sent him a check that day. I tested them out the day I received them and they were just what I had been looking for. I was able to get flash durations on the order of 1/20,000sec. and shoot with the lights 4 1/2 feet from my subjects at F22 with an ASA of 100.
The first subject I tackled with my new system was a house wren family that had built there nest in a nestbox near my home. For this setup, I used an infrared beam device called a Dale Beam to trip the camera. The Dale Beam works by emitting an infrared beam that when broken, fires the camera it is connected to. I placed this unit so the beam was across the entrance to the nestbox. When the parent house wrens returned to the nest, they break the beam and fire the camera, virtually taking their own picture. While I relax in my blind drinking cafe lattes.
Here is an image showing the setup I would use to photograph the house wren nest. This nest was about one mile through the woods from my home, I used a wheelbarrow to get all of this equipment to the site.
And here are a couple of images I made of that pair of wrens.
This next high speed flash image is from a Barn Swallow nest that I photographed last summer. This pair of birds chose to nest under the eaves of a picnic pavilion about 10 miles from my house. A friend had told me about the birds the year before and I made a note to check back the following spring. For this shoot, I decided not to use the Dale Beam because the birds did not have a predictable flight path. So instead I fired the camera myself when the birds were in the area I was setup for. The trick to this type of photography is getting a frame where the wings are in a pleasing composition. I took thousands of pictures to get a few good ones. This one in my opinion is the best of the bunch not only because of the adults wing position but also because of the way all of the chicks are lined up.