Nick West Photography: Flash & Blur

As part of my portrait portfolio for the recent course I attended I decided I wanted to include some flash and blur photographs. I have to say that I am not a fan of it but then I suppose it depends on what the customer wants and what you are trying to do. We did do some shots of a boxer in the studio using this technique and I wanted to replicate it to show that I have grasped the concept.

So what is meant by flash and blur? Well in this instance it is taking a slow speed shot to accentuate movement using a fixed constant light source and a single flash to freeze the last part of the picture. It is not a straightforward shot as the flash, which fires for a fraction of the time that the shutter is open, is triggered as the shutter is about to close. Sometimes this is referred to as the second curtain, the first being when the shutter begins to open. The fixed light is on for the duration therefore the sensor is receiving light for the whole period from this one source, which then causes the blur.

The equipment that you need to do the shot below is: camera, remote trigger (not essential), tripod, fixed light with stand, softbox flash unit with stand, camera mounted flash, black background or plain curtain, light meter and a model naturally!

The diagram above shows how I set up the studio, in this case my loft! The fixed light was at 90 degrees on the left hand side, the flash was facing the model alongside the camera. The light meter read the fixed light at F18, 1/4 sec and ISO 200. I used this setting to tune the power on the flash unit. The next part was setting the on flash camera, a speedlite 550EX. There is a feature on this unit that allows you to fire the flash as the second curtain is closing (the end of the 1/4 second exposure). In the user manual it is referred to as second curtain synchronisation and I had to look it up to press the right buttons on the flash unit to make it work. The flash itself was pointed to the rear of the camera as I was using it to fire the main flash unit via it's photo sensitive cell. So on flash camera is set to fire as the curtain closes and it in turn triggers the main flash unit to freeze the image. As I began to take pictures I slowed the shutter speed to 1/2 sec and increased the F-stop to compensate. This is a question of taste and the speed at which the subject moves.

So now the hard part, composition. What did I want the model to do? To be brutally honest I didn't know other than to move in some direction. I decided to go for a head shot for the sake of framing and the lack of space to get a full length shot in. During the shoot there were a few times the on camera flash did not fire, the batteries were getting low so it was taking longer to refresh the charge. In the end I opted for the model to side step from left to right of the image, this way I got the movement but also a clearly defined image. If you imagine a sheet of paper that you have already drawn a face on, once you have used the free space then you either can't use it again or you have to draw over the top, which gets a bit messy. In this case the paper is the camera's sensor and the blur is the multiple times which you have drawn over the first face. It took a few attempts before I was happy with the shot. I forgot to mention that I used the remote shutter release to take the photo, you can do this by hand or using the timer.

The first image is the planned shot the second is one that I took and the flash failed to fire. I had to adjust the second image in RAW to set the white balance to flash, I had forgotten to set this earlier on the camera. RAW is a format that you can set on the camera and it essentially saves all of the data so that you can do a lot more with the computer later on. I rarely use the RAW file but I do have my camera set to capture both RAW and the JPEG image. RAW takes up a lot of space so it is a personal choice you need to make. My memory card is 16GB so there is always plenty of space.