Flash Technique: Ducking the Shutter

Here’s a little tip about a flash technique I call ducking the shutter. It’s a way, when using a flash, to eke out a slightly faster shutter speed than the specifications of your camera would suggest is possible, without resorting to any sort of high speed FP sync mode.

Sometimes you want to use a shutter speed that’s faster than your camera’s flash sync speed so as to reduce the contribution of ambient light to your exposure. If you know the limits of your shutter you can sometimes manage to do just this.

Basically the trick is to compose your photo in such a way that the parts that are to be illuminated by your flash are placed in the area of the frame that will get flash exposure at the shutter speed you’re using.

The easiest way to find out where those areas are is to take some test shots. Here I put my camera in manual mode chose an (unimportant) aperture and then took a shot (with my flash) of a blank background at different shutter speeds. In this case I triggered my flash with a radio trigger and obtained the results shown below.

Ignoring the light falloff from right to left (the flash was not aimed perpendicular to the wall) you can see how the shutter curtain begins to obscure the frame as the shutter speed increases. The dark areas in this case are the parts of the frame that were not illuminated by the flash. They are still illuminated by the ambient, it is just that at this particular aperture and shutter speed the ambient was too low to have any noticeable effect.

So even though the official sync speed is 250th as long as I position my (flash) subject in the lower two thirds of the frame I can shoot at 1/400th. It is like I am ducking under the shutter to make the shot. If I duck my subject down to the bottom half of the frame I can even pinch 1/500th of a second.

A perfect example of this technique in action can be seen in the photograph below, a de-fished fisheye close-up of a Ferrari parked at the viaduct. This was 1/400th of a second at f/8 with a wirelessly triggered SB-800 at full power through a Lumiquest softbox.

I was shooting almost straight into the sun. Without a flash there was no way I could get a single exposure for both the car and the sky. But placing the car in the lower part of the frame I was able to sync at 1/400th and still get full flash power onto the car, and thus a good balance between sky and car.

This technique also works in portrait mode. Depending upon which way up you hold the camera you just need to keep your subject to the right or left of the frame.

Exhibition Submmissions Update

I'm pleased to record that my submissions (detailed in the previous post) for the NZFM Passion Exhibition have all been accepted. Woo hoo !

My Exhibition Submissions

I am a member of the NZ Flickr Meetup Group an internet based group of photographers who meet up from time to time for the purpose of photography. The group is planning an exhibition as part of the Auckland Festival of Photography and were recently accepting submissions from the members. Judging for acceptance into the exhibition will be taking place tonight - or at least starting tonight.

Full details can be found here, but in short the brief was:

We want you to show us your passion; what makes you a photographer? What makes you a part of this group? Show us your passion and what it means to be a photographer as a part of NZFM. It’ll be a very personal experience for each of us and what’s important to you may well vary from everyone else.... That’s precisely what we want to capture.
The exhibition brief comprises two parts; your image or images as well as a written statement.

I submitted one image for the print category:

“Theatre photography holds a special place in my heart and this image is one of my favourites. A candid shot taken backstage during a performance of "La Cage Aux Folles", which I had a part in, it shows an actor preparing for their next scene.
In some ways this is simply a documentary recording of a particular person, time and place, but for me it is, at the same time, a representation of any actor, it could be any theatre anywhere and at any time. It is an intimate view into a world that I enjoy and which, through my photography, I would like to share with others.”

And three in the digital category:

“Theatre photography holds a special place in my heart. Capturing a live performance (these are all taken during dress rehearsals) presents a particular set of technical challenges. While there is often a huge contrast range, the light can change in an instant and the overall illumination levels are often quite low. Technicalities aside, capturing the right moment is critical, a fraction of a second often means the difference between a hit and a miss. But every now and then you get one where the lighting, the performer, your inputs and the moment come together and catch a little bit of the magic and wonder of theatre. These three images, from three different shows, are ones that I was thrilled to have captured.”

I don’t know yet whether they will be accepted or not, but you can be sure that the blog will be updated once the results are in.