Using flash effectively and learning about lighting is often the “final frontier” in a photographer’s journey to mastering photography.
For many, the challenge is a step too far. The flash gun you bought lives in the bottom of your bag, or worse – in a cupboard, and to anyone who asks, you are a “natural” or “available light” photographer. If you’re anything like I used to be, you really mean that you’re a photographer who knows next to nothing about light! That was me a few years ago, so I’m talking from personal experience.
Until recently, learning about lighting was a hugely involving and time-consuming process. Now, thanks to the instant feedback we get on the back of our camera, it’s easy. It’s just a question of finding out where to go to learn.
I’m going to de-mystify this whole thing a little bit and set you on the way to having fun with light.
To paraphrase famous photographer Joe McNally, “I’m an available light photographer. I use any light I can lay my hands on.”
So let’s put our flash onto our hotshoe. This is a great place to start. Yes, the flash is fixed in position relative to the lens and everyone’s always talking about off-camera flash these days, but we’ve got to start somewhere.
With the flash set on its TTL setting and your camera set to ISO200, put your camera on f5.6 on AV mode and let the camera decide the shutter speed. Take a photo of something. It’s always fun if you can find something (or someone) beautiful, but anything will do. Now set your camera mode to M for Manual and fix the same aperture and shutter speed into the camera that you had just now. Take another photo of the same subject with the same positioning as before. Your two photos should look identical.
Here’s where it gets interesting. We’re going to play around with the shutter speed and see what happens. It’s easy to forget the concept of “STOPS” of light thanks to our modern cameras that we can adjust in small increments, but to review, shutter speed ‘stops’ correspond thus:
… > 1/4 > 1/8 > 1/15 > 1/30 > 1/60 > 1/125 > 1/250 > 1/500 > 1/1000 > …
You can change your aperture in stops too, hence the term f-stops, but we’ll come to that later.
So if you started on 1/160, drop your shutter speed to the nearest stop below that; 1/125 and take another photo (same subject, same position). Then a photo at 1/60, 1/30 and so on until your photo is blown out when reviewed in the back of your camera. Then go back to the shutter speed you started with and RAISE the shutter speed, for example to 1/250. You’ll see the background get progressively darker while your subject remains well lit by the flash. Be careful not to exceed your maximum flash synch speed (see your manual for details)
What we’re doing here is changing the ratio in the photo of ambient light to flash exposure. Every time you use flash in a photo, the final image is composed of some ambient light (i.e. light from any source that you can see with your eyes) and flash light (i.e. light cast from the flash(es) you’ve introduced).
You control how much ambient light appears in the photo with the shutter speed. Take a look at the differences in the photos you took in the exercise above and we’ll go over what’s happening in the next instalment.
Here are some hasty examples. A very unglamorous set of a corner of my untidy desk at enlight photo HQ. I’ll replace these shortly with some glamorous shots of a gorgeous model in New York but until then, these will show you what you should be aiming for. All of these are at ISO200. My AV setting of f5.6 gave me a starting exposure of 1/60. You may find as soon as you turn your flash on and put it in the hotshoe, your system defaults to the flash synch speed. If this happens, simply remember the shutter speed that the AV setting chose and set your camera to M and dial it in.
OK, so here is a photo taken with the flash on TTL, shutter speed 1/60 and f5.6. Note the foreground is perfectly exposed with the flash (albeit with horrible shadows) and the background of the office where the flash doesn’t reach is exposed… kinda just about.
Next up I’ve left the flash on manual, but gone for 1/30. Note the flash foreground exposure is identical, but the background lit by “ambient light” is brighter.
All I’ve changed is the shutter speed to 1/15. Again note how the foreground exposure is unchanged, but the background is even brighter.
And finally, shutter speed to 1/5. Now the background is almost getting too bright. Yet the forground is still lit perfectly with the flash. D’you see how changing the shutter speed has altered the “ambient light”-lit parts of the image ?
So now let’s go the other way. Here the shutter speed is 1/125. So the background is consequently darker.
And finally, darker still with the shutter speed at the maximum synch speed of 1/200. Notice how in all of these shots the foreground, lit by the TTl flash, is identical. Because we haven’t changed the position or the aperture, the flash has actually fired all of these at the same power.
Now your turn… imitate what I’ve done and think through what’s happening.
Resources and cool lighting sites:
- www.orbisflash.com (yep, that’s my website)
- www.youtube.com/enlightphoto
- strobist.blogspot.com (check out the excellent Lighting 101)
- www.lastolite.com
- www.chimeralighting.com
James is inventor of the orbis™, a pro photographer and lighting workshop guru. Watch out for the next part of this series soon, featuring shutter drag and second, or “back” curtain synch.
Main photo – James Madelin demonstrating on the Orbis photowalk in Leeds, September 2010. Image by Matt Dean. All text and other images © James Madelin 2010
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