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 p.1 #12 · As a strobist, how many flashes and battery packs do u have? | |
As many as the shooting situation allows or requires  I shoot mostly PJ style situations and informal portraits with hot shoe flash and in most situations a pair of flashes suffice. I've used a pair of hot shoe flashes since the 1970s, learning the technique of using them to shoot wedding receptions and similar "candid" situations working for the photographer who introduced and popularized the idea of dual flash to wedding photography: Monte Zucker.
Two flashes, one on a camera bracket, and a second on a rolling stand ( a modified IV ) stand can cover most PJ style candid situations where flash is needed. In situations where only one flash can be used having it up 12-18" above the lens on a bracket results in natural downward angle to the light and a flattering "mask" pattern of highlights on the face the brain recognizes immediately as a face...
Single flash with a bracket - creates flattering "butterfly" style (i.e centered on nose) pattern which is very flattering in a full face pose.
When the subject turns their face obliquely to the camera the way the bracket positions the flash results in the nose shadow falling out of sight directly behind the nose.
SIngle flash w. diffuser on bracket, taken standing on a chair with the diffuser close to the ceiling for spill-fill to keep the background light.
SIngle flash w. diffuser on bracket outdoors. Bright background selected to make the light clothing less distracting.
In both shots the flash is actually the "Key" light which creates the highlight pattern on the face. In the top shot indoors splitting the flash so some bounced off the ceiling provided the fill for the shadows. In the bottom shot the sky she was facing provided the fill. So while one flash was used as the source of illumination the lighting effect is a result of controlling the direction of the brighter "key" component creating the highlights which exposure must be based upon, while at the same time manipulating the level of fill. Control of lighting requires independent control of the key and fill components whether they are produced by one flash indoors or one flash and ambient indoors or out.
When a second flash is added to the lighting scenario indoors the simplest way is to use it as backlight. Its simple because placement of the off camera flash isn't really very critical because its just creating rim lighting. You can simply park it off to the side and shoot with as you would with a single flash on a bracket.
The basic goal photo is tricking the brain of the viewer into thinking the 2D pattern of contrast created with the lighting depicts a 3D object. If you were to take a still life subject and light it from all angles you'd find the greatest illusion of shape occurs when the key light comes from behind the object and you are viewing it from the shadow side.
But the dilemma with portraits of people is that the area most critical to delivering the message of the photo -- the eyes, mouth and front "mask" of the face -- wind up in shadows. But as noted above in the single flash shots if the frontal flash -- which is actually acting as 'key' light -- is raised 12-18" above the eye line of the subject it will produce a very flattering lighting pattern. What makes a lighting pattern flattering in a portrait? That is subjective but light in the eyes and mouth and the absence of a distracting nose shadow are on the top of my criteria list.
What makes the simple two flash backlighting scenario effective, when the frontal flash is raised over the heads of the subjects for flattering modeling is that the illusion of 3D in the overall scene is created by the rim lighting at the same time the downward direction of the frontal light models the features of the face in a way that is attractive in large part because there is no dark distracting shadow hanging off the nose. You'll also notice that in the action shot of the girl dancing the fact the two lights meet in the middle has eliminated the characteristic fall off seen with single flash on camera. Even lighting could be obtained by bouncing flash off the ceiling, but it would have all the snap of an overcast day with dark eye sockets.
Here's a two flash example where I did bounce the flash on camera to better illuminate the space and keep the foreground from becoming over illuminated:
My conceptual model for lighting with flash is a stage, putting whatever is important in the spotlight and letting all the less important stuff fade into the footlights to the degree they can there to establish context for the action, but don't distract from it. That's the balance which makes editorial / PJ style shots effective or not. In the shot above I placed the off camera flash on the stage out of frame on the right to make the it the brightest focal point, using the guy in the foreground to frame it, creating the illusion of space via contrasting size.
A two flash shot from the same event. The goal was to create a wide establishing shot to set the scene for the close-ups which would follow. For that shot I walked all the way around the room to place the off camera flash and then back to take the shot. Aiming the off camera light at the guy in the checked shirt was intentional to pull attention in that direction. Also the intended audience would then recognize that the couple sitting next to him is the senior pastor of our church and his wife.
In the shot above I used the couple in the foreground as both a compositional element to create the illusion of depth and space via contrasting size and as a flag for the off camera flash.
To get flattering lighting on a face is necessary to control or predict the angle of the face, particularly the nose which creates a distracting shadow, to the "key" light which creates the shadows. At the same time the face is flattering the most by shooting into shadow side (i.e. short lighting). In candid situations its mostly a matter of situational awareness of the the ambient lighting how best to use it, and when to augment it or in some cases overpower it to produce a result which via contrast focuses attention in the photo on what is most important.
Barry Black, the Chaplain of the US Senate and former Chaplain for the US Navy was a guest preacher. Getting a flattering shot of him was just a matter of finding the spot where he'd be in a flattering oblique angle in flattering short lighting from the stage lighting at the same time... Situational awareness of the ambient lighting and predictable action....
I knew from previous experience that the stage lighting had too much contrast for the camera and was off color due to the magenta cast of the shadow side stage lights so I used flash gelled with 1/2 CTO as fill to open up the shadow side, matching the WB to the stage lit highlights and eliminating the off color shadows. Preachers are animated and to took several attempts to get a good oblique view. Here's one of the near misses...
That slight difference in facial angle relative to the camera makes a big difference in the appearance in the face, which is why finding the spot where the face is in flattering light and the camera angle makes the face look balanced and symmetrical are the key ingredients for a flattering "candid" shot. I shot him from the other side just to illustrate how not being aware of how best to use the ambient light would make him look...
From the "broad" side of the dominant key light his face looks much wider. He's a handsome guy who looks good from any angle, but I think the short lit view flatters him more.
The short lit oblique combination of lighting and pose is flattering because it can make a wide or asymmetrical face look slim and symmetrical, the two traits faces considered attractive have. People who are selected as models and make the big bucks generally have faces which will viewed full have those two qualities. For everyone else capturing their face in short light in an oblique view will usually result in a portrait which looks more flattering than what they see every morning in the bathroom mirror. Having learned that very early I always look for opportunities to use short lighting when shooting indoors with flash.
I saw such an opportunity when photographing a going away party. The guest of honor was talking to the couple long enough from the same spot for me to wheel my off camera flash on the IV stand around to the left so it was 45 degrees from his nose. Aligning an off camera flash without modeling lights is simple if you just stand behind it and put the light between your eyes and the subject. That way you see exactly what the light will hit. Move it until all you see is a perfect oblique angle of the face and you'll get perfect short lighting on the face: very simple. Then you just walk back around to the other oblique view on the shadow side of the key light and fire.. In that case I used the tall guy in the foreground to flag the off camera flash from view and adjusted the ETTL ratio so fill from the camera was minimized.
All the above shots where done with wireless ETTL with the Canon system, with no need for additional radio triggers. I use the same gear and short lighting strategy for portraits, but shoot in M mode rather than ETTL so the exposure and the backgrounds will be consistent shot to shot. Set up is identical to what I used with single power flashes back in the 1970s.
Fill is on the camera, so its distance is the same as the shooting position. I like to shoot from about 8ft because I find that distance produces flattering perspective. To get a 3:1 lighting ratio the key light needs to be 1 stop (2x) more powerful than the fill it overlaps 2k+1f:1f = 3:1 reflected ratio on the face. To make the key light 2x brighter I put it at a distance of 5.5 feet, from nose to center of the diffuser, which happens to be my arm span. Placement of the off camera light is done via the "WYSIWYG" method of standing behind the light as its moved. Because the distances of the lights is always the same, so is the exposure: f/8 at ISO100 with both flashes at 1/2 power (for faster recycle and longer battery life).
The white towel is my exposure meter. Held next to the face it will clip at the same time the red channel in the skin or any white clothing, eyes, teeth start to loose detail. So taking a test shot and checking the clipping warning in the playback is a way to confirm all the settings are correct.
The advantage of using M mode in static situations is consistency shot-to-shot. All TTL metering systems react to scene reflectance and just a subject changing the angle of their body will cause a shift in reflectance and exposure which the metering may not compensate for perfectly. Once set the exposure in M mode will produce perfectly exposed subjects with identically toned backgrounds regardless of how the clothing in complexion of the subject changes. Exposing for a dark skinned subject is the same as a light skinned one. Just consider that both might be wearing the identical dark suits which which shirts. The light set-up needs to capture detail over that full range and when it does the detail of the faces will also be rendered normally...
The key to that, technically, is grasping the concept of controlling contrast via overlapping key light over even fill. Beginners tend to think of key and fill as opposing forces and place the two lights on opposite sides. But the reason fill is needed at all is because the camera sensor can't record the full range of the scene. Expose for the highlights, as you must in most situations, and some shadow detail will be lost. The role of fill is to lift up the shadows to where the camera can record detail at the same time its also retaining the highlight detail. That can only be done with flash if the fill source for the shadows does not overlap the key source.
The classic dilemma outdoors is dark eye sockets. What happens if you add flash to the front of a face lit that way is as the eyes in the shadows get more light so do the ambient highlighted cheeks. Reducing the shutter time will bring the cheeks back below clipping, but will also reduced the amount of ambient fill reaching the eyes, requiring more flash. Its like a dog chasing its tail. Flash replaces ambient, but the contrast between eyes and cheeks does not change.
The solution to the dilemma is to get the front of the face entirely in the shadows. Then the shutter can be set to correctly expose the sun lit parts of the clothing, background, and backlit hair while the flash INDEPENDENTLY lifts the shadow side up to match the sunlit parts. The counter-intuitive part of the process is that a correctly exposing the ambient light with a digital camera in a backlight situation results in a photo like this because the limited range of the sensor can't handle the greater contrast of the scene:
Without flash average metering or a human looking at the playback would opt to overexpose the highlights in order to allow the camera sensor to record the more important midtones correctly; i.e as perceived by eye with adaptive vision. But with no ambient light hitting the front of the subject its easy to independently control the foreground illumination with the flash, raising it to a level which creates a balance in the photo similar to how a viewer would perceive the lighting in person.
The shot above is from a High Speed Flash test I did where I simply reached up and turned on the flash set to FEC=0. The camera 35 zone metering system was able to sort out how to match the foreground with the brightest ambient highlights to keep everything below clipping. But the key to making the flash exposure work was to first keep the ambient highlights below clipping in Av mode by using - 2 EC.
Again grasp that flash isn't "fill" its the key light because it is creating the highlight pattern.
In that single flash "fill flash" shot the flash created the highlight pattern which defines the 3D shape of the face. The shadows where the flash didn't hit were illuminated by the ambient "fill" light from the sky wrapping around the face.
Again I stress the importance of direction of the flash: its needs to come from above the eye line of the subject to create the flattering "mask" pattern and avoid a distracting nose shadow. Using a flash bracket might seem cumbersome, but the payoff comes from the fact is places the flash exactly where is needs to be for flattering modeling of a face whenever it is the source creating the highlight pattern on the face.
Since its a frontal view and most of the face is highlighted and the white clothing is reflecting light up into the shadows they are open and reveal detail. But when a subject obliquely in backlight from the sun the shaded side of the face filled by the sky can become too dark making the lighting look harsh and less flattering. In direct sun the shady side of the head will be 3 stops darker than the sunny side. In terms of lighting ratios that makes the incident light in the highlights 8x brighter resulting in a 8:1 lighting ratio which is quite harsh.
To short light an oblique view of a face the "key" highlight producing flash needs positioned 45 degrees from the NOSE (not the camera). Since the nose is pointing 45 degrees to the camera the key light winds up at 45 + 45 = 90 degrees off the camera. Indoors with a single flash positioned that way the side of the face facing the camera would have no detail. Outdoors when the flash exposure is adjusted to match the ambient the side of the face will be about 3 stops darker, the same as it would be in just the ambient light.
Opening the shadows outdoors requires the same strategy as indoors: add a second independent source of fill, ideally from the direction of the camera creating a situations where exposure can be set to the highlights while the shadows can be lifted up to where the camera can record detail by fill without adding any more light to the highlights. The difference outdoors is not as much fill or key flash is needed (versus shooting at the same distances indoors) because the sky light is illuminating the front of the face with soft wraparound light which augments both lights.
The wraparound effect of the sky in an outdoor backlight situation has the added benefit of minimizing the need for huge modifiers on the flash. To illustrate that a few years ago in a thread about modifiers outdoors I grabbed by two 580ex on bracket and stand, took them outdoors and dragged the ever reluctant in house model out of the garden for a test shot...
The shot was taken in Av mode with ETTL wireless flash control using fill on the flash bracket as Group A and an off camera flash about 6ft to the right as Group B key light. No diffusers were used. The point of the exercise was to show how the contribution of the soft wrap around light from the sky modifies the effect of the direct flash, which is really doing little more than kicking up the ambient light a stop or so.
Without any flash at all the front of the face would be 3 stops darker than the correctly exposed sunlit highlights. Adding about 1-1.5 stops of light to entire face with the fill on camera opened up the shadows. Then the off camera flash, which overlapped both the sky and flash fill, simply needed to raise the light level one stop above the shadows (incident) to create a 3:1 reflected ratio on the front of the face. So without any diffusion at all its possible to get soft looking lighting simply by knowing how to make the flash and ambient work together instead of fighting each other.
Up to this point all the examples have been with two flashes, but outdoors the ambient light acts in several different roles -- backlight, background light, and fill -- all at the same time so when used thoughtfully two flashes outdoors can produce the same net effect as 4-5 indoors. That's something those starting out with minimal flash gear might want to keep in mind.
There is ambient light indoors, but in most cases it will come from a very unflattering direction directly overhead, or be a different color temperature than the flash. Gelling the flash to match the ambient is a possible solution to the color match problem. I do that when shooting stage presentations, putting a 1/2 CTO on the flash to match the ambient as I did in the shots below of a teen talent show, using on flash up on stage to the left plus a second on the camera bracket:
But often the ambient lighting is fluorescent, which comes in a wide variety of color temps. When dealing with fluorescent lighting I'll usually either keep the flash off and set WB to the ambient off a gray card, or use enough flash to overpower the ambient. When asked to document the crew of volunteers who handle food prep at my church I scouted the kitchen in advance and found it had plenty of light but was flat and unflattering. So I opted to overpower it with flash. It was one of the view situations where I used more than 2 flashes.
Because I didn't want the backgrounds to look like a cave I added a third flash as Group C to light the background. With the Canon system used in ETTL mode Group C is intended as a background light. It is metered and controlled separately from A:B ratio with a secondary FEC setting. The main FEC setting will control the exposure of the A:B lit foreground. Group C, when set on the flash at 0 should (in theory) match the background level to the foreground, and adjusting the FEC for Group C will alter that balance as needed.
I don't add a light to a scene without understanding how it will affect eye movement in the photo. Key and fill work together to create the contrast dynamic which pulls the attention of the viewer naturally to whatever contrasts the most. On a medium / dark background the role of the key light is to pull the viewer to the face. Fill will control how dark the shadows are and by virtue of light and dark contrast how strongly the highlights attract attention. So lighting a scene with flash is more an exercise like lighting a stage - use the light to contrast what is most important -- than trying to light the space evenly. In most candid situations with flash the stage is predominantly dark and whatever gets the most light attracts the most attention. So when opting to add a third or forth light I ask myself whether the contrast it creates will help draw the viewer into what is most important or pull them away from it. The answer to that simple question guides the placement and intensity of the light. Less is usually more effective...
Chuck
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