You know which one I’m talking about: grilling with friends, watching the parades, hitting the pool, and of course, fireworks!

One of the things I love best about the 4th of July is the chance to get my camera out and photograph fireworks. There’s a lot of tutorials out there on how to take good pictures of fireworks–you can find them if you look. One of them you might find is the tutorial I wrote last year on a different technique for capturing the pyrotechnics using a long exposure and a focus shift.

This technique breaks with the traditional method of capturing fireworks by creating a dynamic change in the point of focus during the exposure. This change in focus creates incredible, abstract images of color and light.

Here’s what I put together last year using this technique.

The technique is quite simple. Here’s how you do it:

All you need is a solid tripod, an SLR camera, and a long lens. For me, I use my 100mm lens on a 40D, which is the equivalent of a 160mm lens.

1. Try to set up as close to the fireworks as you can. You want to fill your frame with the fireworks, so get close, and use a long lens.
2. Shoot in manual. You can’t let your camera try to meter for these constantly changing bursts of light–either it won’t be able to keep up, or it will try to properly expose the pitch black night sky, completely blowing out the bright light from the fireworks.
3. Use your lowest ISO. For me, that was ISO 100. You’ll be doing longer exposures, so you want the least amount of digital noise possible in the final image. You might even consider turning on your camera’s own long exposure noise reduction option for this.
4. Start with a shutter speed around 1 second. I used 1 second for all of the images I shot last year. At that shutter speed, I found that an aperture of f11 or f14 worked well to produce well exposed images. You can experiment a bit with this, perhaps trying shutter speeds anywhere between 1 and 6 seconds.
5. Use manual focus. Make sure you flip that little switch on your lens from AF to MF. This is where the magic happens. After you press the shutter button, you’ve got about a second or so to change the focus during the exposure. Large changes in focus work best. You can start with the focus set up close and shift it towards infinity during the exposure, or you can start at infinity and move it back up close. Try both. Try going from one end of the focus range to the other and back during the same exposure. With focus at infinity, the light from the fireworks will produce sharp lines on your image. With the focus up close, the light creates soft, colored balls or stripes of light. As you shift from one end of the focus range to the other, you produce incredible, abstract images of color and shape.
6. The last step is something to keep in mind the whole time you’re exposing and shifting focus: don’t rock the tripod.