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Meet Teddy. Teddy came around for a portrait session and I thought it would be wonderful to shoot him against a window, using it as a backdrop. Putting my camera in Matrix (evaluative) metering mode and on aperture priority, I dial in my required aperture and let the camera take care of the rest.
As you can see from the scene, there is a large dynamic range in the shot. The camera has done it's best to not blow out too much of the window detail, but because of this the teddy is too much in shadow. The camera tried to more or less average the exposure between the window and the subject.
One way of "fixing" this, is to put my camera into spot metering mode and meter off Teddy's face. When I take the shot now, Teddy is perfectly exposed. But in order for the camera to lift Teddy from the shadows, my exposure choice has dramatically blown out the window detail behind him. The camera just doesn't have the dynamic range to expose both objects correctly!
The lighting setup for two shots above is shown below.
This is where fill flash comes in. With fill flash, we should be able to add light to the scene, lifting teddy from the shadows whilst still retaining detail in the background. Effectively what I want to do is meter for the background and then use my flash to light the foreground, balancing both light sources to each other.
Fill Flash - On Camera Flash - Direct, Bounced and Diffused
The simplest way to use fill flash is simply put my camera into aperture priority mode, switch it into matrix metering and my SB800 flash into TTL mode (in fact it should switch to TTL-BL). This is a fully automatic mode, where the camera in conjunction with the flash makes all the decisions relating to exposure and flash power. The above two modes combine to give you a balanced fill flash, so both camera and flash try to work together to maintain the exposure in the background and use the flash to light the subject, which is what we want
The exposure here is obviously much better. Teddy has been lifted out of the shadows and the background detail has been retained. Exactly what we wanted! This is a super result from a pure automatic mode, making it almost fool proof. For me however, there are some problems with this shot.
The flash is directed straight at Teddy, so he's a little flat and washed out, with no shadows. There is also a catch light directly in the centre of the eye, which is unappealing. A very simple fix to this is to use bounced flash. By tilting the head upwards, approximately 50 degrees, I can bounce the flash off my ceiling and light teddy using this softer light. So leaving the camera on the exact same settings, where it is making most of the creative decisions, I simply tilt the head upwards and click the shutter.
Exposure wise, both scenes are more or less the same. However, the second shot is far more appealing. There is modeling/shadow on the face and it no longer looks flat and washed out. We've also lost the harsh centered catch light in the centre of the eye.
When shooting outdoors, I sometimes hear photographers say that it's just not possible to use bounced flash. Whilst I don't necessarily subscribe to this idea, I do agree that it can be difficult at times to find surfaces which can be used to reflect the bounced flash. Personally I always carry a hand held reflector with me… but I digress! So, let's imagine that it's simply not possible to bounce the flash and we are forced to shoot it directly. In this case, a diffusion dome comes in extremely useful. As discussed already, a diffusion dome softens the light considerably and is perfect for situations such as this.
In fact, we can combine the diffusion dome and the bounced flash methodology to give us even softer pleasing shadows.
Hopefully you'll agree that from a lighting perspective, this is probably the most pleasing? The shadows are soft, the exposure is good and the lighting is balanced between window light and flash. All positive points!
Just so we're clear on the lighting setup for the last four portraits of Teddy, I've enclosed a lighting diagram below. In all cases Teddy was back lit by the window and lit by an on camera flash. However, the flash has been used direct, bounced, diffused and different combinations of the three.
Off Camera Flash
So far, the flash examples I've shown have all been with the flash mounted directly on the cameras hot shoe. However, to really push the boat out creatively, we really need to mount the flash off camera in a different position. This opens up the number of creative possibilities but also adds an additional level of complexity.
For one, we need to find some way of firing the flash when we depress the shutter. A simple way is a PC sync cord, which goes into your camera's sync port and connects directly into your flashes sync port. This obviously assumes both camera and flash have one, which is not always the case. With this method, apart from a signal to fire the flash, there is no other transfer between camera and flash, so you can no longer use a lot of the automatic modes.
Another solution, is for a TTL hot shoe adapter, which effectively extends your hot shoe, by attaching to the hot shoe on your camera and then to the bottom of your flash via a cable. With this method, the camera and flash still have the ability to talk to each other, so auto exposure modes can be used successfully.
Some flash systems use wireless flash modes, like the CLS (creative lighting system) offered by Nikon. With this method, you can use one flash, to control and fire the other flashes. This system can get pretty advanced and very complex, very quick. You can also buy third party infrared triggers which can be used to communicate between camera and flash. Again, the draw back of these is that like the sync cord, they are used simply to fire the flash. No data transfers are sent to and from the flash/camera, so no automatic modes can be used. The flash power has to be controlled manually.
A final mode, the one that I used and prefer is a wireless radio trigger. I personally use Pocket Wizards, but there are cheaper, alternative third-party brands. One pocket wizard sits on my cameras hot shoe and the other plugs into my flashes sync port. With these I can place my flash anywhere at all and fire it from my camera.
Fill Flash - Off Camera Flash
With the flash positioned to the camera's right (subjects left), I now have one issue relating to how I control the output power of the flash. The only solution for this is to use a hand held light meter, which can meter both flash and ambient light. So I now switch both my camera and flash into manual mode, where I have complete control over shutter speed, aperture and flash output power.
For the shot below, I used the hand held meter to meter for the ambient light in the background and dial in the correct aperture and shutter speed. The flash at this point is still turned off.
We are more or less back at the beginning, in that Teddy is underexposed. However in this case the exposure, rather than trying to average between the back light and Teddy, it is based entirely on the window, so Teddy is completely underexposed.
At this point we now introduce flash. As everything is manual, I'm now able to decide exactly how much flash power to use, depending on what ratio I want between the window light and flash. For the moment, let's look at a 1:1 ratio. I turn on the flash, fire it and take a meter reading. Based on the flash reading and the previous ambient light reading, I calculate the difference in stops between flash and ambient. I then dial down or up the power on the flash accordingly, so I have the same flash intensity as I do ambient light.
Obviously as the camera is off to the side, we now have a lit side of the face and a shadow side. This ratio of light and shadow can be used to produce many different effects and lighting styles (broad lighting, short lighting, Rembrandt etc.) which I won't be discussing just for the moment. But one thing that is very noticeable is how harsh the flash is. Can you guess why? Yes, it's because the flash is directly pointed at Teddy albeit, off to one side.
A simple fix for this is to bounce the flash. In the last shot, I bounced the flash and used the diffuser dome to soften the shadows even more. The more astute of you may notice that in this shot, Teddy looks a little pinker than he has in previous shots. The main reason for this is that the wall in my house is Red and as the flash bounced off that, it changed the colour of the light that was cast.
Overpowering ambient light with flash
Using the same setup as the previous off camera flash shots, I can try something different with Teddy. Rather than having a 1:1 ratio between ambient light and flash, I can also change this ratio. For this shot, I meter once again for the background, but rather than dialing the correct values for aperture and shutter speed into my camera, I decide to underexpose the scene by closing down my aperture and stopping down by two stops. I adjust the power of my flash to match this new exposure and take the shot.
The flash is now the main source of illumination and I've made it look like the shot was taken late in the evening rather than at mid-day. Simply by changing this ratio, the position of the light relative to the camera and the harshness/softness of the light, we can pretty much create the lighting that we want.
At this stage Teddy is pretty bored with posing the way I've had him posing. So let us change things around. For the next series of shots, I'll place Teddy side on to the window, so that this time, one side of his face will be illuminated by natural light.
Previous (Practical Flash) | Next (Fill for side lighting)
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