Registered: Nov 18, 2002
Total Posts: 8545
Country: United States
Indoors manual preferred mode for the camera with flash because in Av low light levels may cause the shutter to slow below what can be hand held and in Tv the camera controls aperture and DOF, taking away an important creative element. In M mode on the camera the metering still works to control the -2 ....|.....+2 indicator so you can use it to arrive at the same "best guess" on exposure via camera metering manually.
So set your aperture for the desired DOF, adjust your shutter for correct exposure of the ambient via the over-exposure warning, then turn on the flash and adjust it in ETTL via FEC, again using the over exposure warning as a guide.
Outdoors where flash is the secondary source of light its role is to try to reduce contrast of the scene so when the highlights are exposed below clipping there is shadow detail. The range of the scene can only be reduced if the flash does not overlap the sunlit parts. Use the sun as back/rim light with the face in the shadows, then lift the shadowed face, which is illuminated with soft light from the sky which is 3 stops darker than the sunny side, out of the shadows with the flash. The flash actual winds up performing the role of key light in that situation: it creates the highlights on the face while the fill from the sky illuminated the parts the flash does not hit. Outdoors use Av and EC to adjust the ambient background and FEC to control the flash lit foreground. Keep the flash set to high speed FP mode and it will shift automatically whenever the shutter speed exceeds the camera x-sync limit. M can also be used on the camera to keep the background exposure consistent.
Control of light direction relative to the face is the essence of lighting and moving flash off camera off the camera is a like double-edge sword: if you don't know where to move it to get a flattering result then net result can often be less flattering than flash on a bracket over the lens. The critical factors in flattering a person in a photo are light in the eyes and mouth area so the viewer will make and hold "eye contact" and react emotionally to the expression on the front of the face of the subject in the photo. The second objective is to model the features of the face in a way that seems natural. The brain gets its clues about shape in a photo from the contrast pattern and the size /shape of the shadows objects cast. If there is a long dark shadow hanging sideways off the nose the nose will be perceived differently than if the shadow is light in tone and falls along the base naturally modeling its shape.
Since most natural and artificial light comes from overhead most of the time, flash also will appear more natural when it comes from overhead also. The light in your shot is more like what you'd get with it facing a rising or setting sun when the sun is low in the sky. That's OK if it fits the context and goals of the shot but can come across as flat an artificial if the context is missing. There are no rules, just cause and effect and low angle lighting doesn't make a face seem natural, simply because we are accustomed to seeing faces lit from overhead.
In landscape mode the flash head is above the lens by about 6" which isn't high enough to produce much downward direction to the light. Raising a single flash using a "camera-flip" bracket an the OC-E3 cord is an ideal way to get a more flattering downward angle to the lighting. Wedding shooter who used single flash for most shots discovered about 50 years ago that raising the flash directly above the lens axis solved the problem of distracting sideways nose and head "halo" shadows by causing most of the shadow down and out of sight. The head shadow disappears below the shadow line and the nose shadow falls directly under the nose where rather than distract it actually helps to hide the nose holes which are even more distracting (if camera position is too low relative to the face). Without any distracting shadows there's only a minimal need for diffusion for the simple reason there aren't many shadows to worry about. The net result is more flattering lighting in "candid" unposed situations when flash is used...
Beginners tend to want to move the flash off camera without giving much thought to the pattern of light, but when you move a flash to the side you also need to be able to control or predict the orientation of the eyes and nose to the light to get flattering results (i.e. light in both eyes and avoid creating a distracting nose shadow) and control the lighting ratio to control how dark or light the shadow look. The human brain gets most of its clues about 3D shape and texture from the shadows, and how light or dark the shadows cause the lighting to seem "hard" or "soft". So before moving the flash off the camera axis you might what to ask how the shadows the off camera light will be filled to creatively control the mood of the photo with the lighting ratio.
If you have your first flash mounted on a bracket its ideally positioned as a source of fill for the two most effective two-flash lighting scenarios: 1) backlight 2) short lighting.
When I can't control or predict the direction of my off camera flash relative to the face of the subject, or am shooting full length or action shots, I'll simply move the off camera flash behind and to the side just out of camera view. The flash on the bracket provides downward direction and modeling to the front of the subject and the flash in back creates a greater illusion of 3D via the visual separation of foreground and background the rim light creates:
Technically its a no-brainer, the same as using one flash. Just set the ETTL A:B ratio and ride herd over exposure with FEC.
In some candid situations people will be standing in one place long enough to position the off camera light for a flatting short lighting pattern:
More often that not is a matter of picking the camera position where I can capture a flattering angle of the face, then setting the light where I know it will create a flattering short lighting pattern, then waiting patiently for the person to turn their face back to that positions. Knowing where to put the off camera flash in those situations isn't too difficult, if you realize the angle that matters for key light placement is not where the flash is relative to the camera, but where it is positioned relative to the NOSE and EYE SOCKETS. Getting a flattering short lighting pattern is a no-brainer if you put the off camera flash so its 45 degrees from the nose and a foot or so higher than the eyes so there is light in both eyes (not shaded by the brow) and the nose shadow falls down along the side of the nose.
The above examples are intended to give you some ideas where you might want to go next with your flash. I suggest as a first step getting a bracket and OC-E3 cord and learning how to exploit what can be done to created flattering lighting with a single flash with diffusers and bounce. Its a valuable skill to learn because in many situations its only possible to use one flash. Then all you will need to create a logistically simple two light location lighting solution is a second Canon flash and a stand. See my tutorials on Canon flash which cover this and many other aspects of flash use including how best to use high speed FP mode outdoors… LINK.
Chuck
