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 p.1 #1 · A Natural Baseline for learning lighting... | |
To me photography and lighting are pretty simple to understand. What is more difficult is understanding why beginners struggle learning it. We see and react to lighting every waking moment so why it is so difficult to figure out where to put a key light and that fill is needed? Because our brains adapt our perception differently than the camera records it.
We wound up on the top of the food chain because of the way our visual system — eyes recording, brains processing — see the world around us. The retina of the eye has a fixed range like a digital sensor but the pupil of the eye constantly adapts to brightness as it scans a scene. Psychologists use photographs for eye motion studies have discovered that the perception process is a sequence of saccades (jumps) and fixations on focal points which contrast. The brain processes the information at the focal points but not in the areas it jumps over rapidly. That was discovered by showing people photographs with foreground and background content, all in similar focus, then later asking them to list everything the remembered seeing.
When I first read that in a psychology paper I had an epiphany because it help me understand why beginner wind up with so many distractions in their photos — they see them but the brian filters them up because they are fixating somewhere else, usually the front of the face of the person or some other object in the foreground. It didn't take a great intuitive leap to figure out that using a wide aperture on the camera to isolate one area of the scene works the same way in a photograph to force the viewer to look only at that spot.
I was fortunate to have learned lighting working Monte Zucker in my callow youth. At that point it been making photographs for several years but really didn't have a clue about how to light a face in a natural way. In the late 60's Zucker came up with a clever marketing "hook" which set his work apart from everyone else in his local market: he started using window light for his portraits and marketing it as the "Old Master Painter" look. He hand painted a couple background in that style and used a north facing window and a reflector.
If you have every used a north facing (in US) window for lighting you probably grasped a few things immediately: you couldn't move the key light, the light came from the sky above to model the face, which you had to turn into the light to put the pattern on it. What is the only variable in that situation? Turning the face and body into the natural key lighting.
Zucker taught thousands of other wedding photographers that simple window lighting technique. He never discussed where to put the "key" light because it wasn't a variable. That made it easier for the student to understand what angle of light to the face looked most pleasing to the eye — when nose on the face was 45° to the window and direction of the light and the face was lifted so it reached into both eyes.
http://super.nova.org/DPR/Window/Subject.jpg
Then it was simply a matter of walking around the face with the camera to capture that pattern with reveals the 3D shape of the face quite naturally full face:
http://super.nova.org/DPR/Window/WindowFF.jpg
... obliquely...
http://super.nova.org/DPR/Window/WindowOblique.jpg
... or in profile...
http://super.nova.org/DPR/Window/WindowProfile.jpg
...without moving the subject or the light.
It all seemed to be so ridiculously simple once explained and that's exactly why Zucker became a renowned teacher. He wasn't university professor teaching his students every variation of lighting, he taught others how to create the same "Old Master" look in their portraits with very simple tools — the camera, a reflector, and a window.
It is, admittedly, a very limited approach to doing portraiture "creatively" in terms of exploring different lighting patterns and background choices. Given the way a window works and the shape of human heads which shots lit that way wind up being "short" lit on dark backgrounds.
My mentor Monte was one of the least technically oriented photographers at his level I've ever met. Like a pro golfer he'd use whatever brand of gear a sponsor would offer him because gear wasn't a critical factor in the style of photography he did. A pin-hole camera would have worked for that style of photography, in some ways even better by eliminating the need to vignette and blur the edges with black masking tape applied the the lens shade.
His approach in using window lighting was in large part a marketing gimmick to set his work apart from others. In the beginning he won PPofA competitions because it was different, at the time. His winning the competitions got him noticed, which led to his sideline as a teacher — which paid better and was more fun than shooting weddings week after week to make a living.
What I observed assisting with his classes and watching the reaction of the students and their before and after instruction results made me realize the window approach ways also a very simple baseline from which to learn lighting technique because there is only two variables:
1) Move the face into naturally flattering light, a task simplified by the fact the light is already streaming through the window at a natural downward angle.
2) Move the camera a round the face to capture balanced views of it:
Full face - nose directly at camera ears appearing similar in size and higher than the eye line so as not to look up the nose (because the view from the top is more flattering)
Oblique - far side not disappearing or not looking to wide either. Start with the > notch on the far side profiled then move left/right/up/down from that starting point to find the spot where the face looks balanced on both sides (which will be highlighted by step 1) and the camera isn't low and looking up the nose.
Profile - The face is cut exactly in half by the camera angle with no odd bits beyond the nose hanging out and breaking up the clean line of the forehead - nose - mouth - chin.
Will that teach you everything you'll every want to know about lighting a face? No of course not. But if you are just beginning to try to sort out how lighting works to model a face naturally as I was 40 years ago you may find that if you try that approach and understand why it works you should be able to try everything else and understand, by comparison with that starting baseline, when something else looks more natural and flattering or not.
The point of the exercise here to get away from the notion of lighting techniques being good or bad and instead thing in terms of whether or not the lighting in a photograph looks natural and when on a face flattering.
What isn't obvious with window light is that when it is most flattering on faces it hits at a 45° downward angle. If higher than 45° the brow will shade the key light from the eyes. If much lower than 45° — where the sun is in the sky at 10AM and 2 PM — the shadow clues on the face are cast sideways, something only seen in nature in early morning and in the hour before sunset.
A mistake beginners make with flash is putting their key light too low. A 45° downward angle isn't always the perfect angle, but it's a good starting baseline for placing any key source (sun, skylight or flash) if you want light in the subject's eyes. If you don't want light in subject's eyes raise the key above 45° and they will be shaded. Put the light below 45° and it will look more like morning or afternoon sunlight. Not good, not bad, not unnatural, just similar to morning or afternoon rather than mid-day natural lighting.
What you will eventually notice — sooner rather than later if you try a window — is that once the nose of a subject is oriented to a "key" light placed 45° above the eyes and 45° to the side you don't need to change pose or light position to capture full, oblique, and profile views. Don't get hung up on what those patterns are called, just recognize what Zucker showed thousands of wedding pros — it's one of the most flattering ways to light a human face.
Not everyone is born with a perfectly symmetrical face. If not a full face view will make that obvious. An oblique or profile view will hide the "natural" asymmetry of the face and can turn a lopsided one into a more attractive looking one.
Lighting is like carpentry in that it's easier to do when the wood isn't warped. An experienced carpenter confronted with a pile of twisted 2 x 4's and the task of creating a straight wall will alternate the direction of the warping in the wood so wind combined the forces will balance each other and the wall will be straight. What the combinations of light and facial angles do perceptually in a portrait is similar.
The fact we perceive a face as 3D in a photo is an optical illusion. The 45/45 key light angle looks natural because that's the angle we see things in most of the time. With a perfectly symmetrical face in a full face pose a light placed to the side at 45/45 will put more of the face seen by the camera in shadow than in highlight. But because the brain is attracted to and fixates more on the highlighted side the brain will think the highlighted side is larger.
Lighting ratio play a role in the perception of symmetry. If you were to light a perfectly symmetrical face from 45/45 and only change the lighting ratio from fill = key to only key with no fill (except that bounced from walls and ceiling) what you will perceive is that as the shadow side gets darker the face looks more lopsided. That perceptual cause and effect is obvious with no fill, but have you ever connect the dot between that and how to make a naturally lopsided face look more balanced in a full face head shot?
If a face is naturally wider on one side if the key light is placed on the side which looks smaller in flat light the face will look more balanced with the key light is placed on the narrower side at 45/45. That's a trick Zucker taught me.
The first thing I do when meeting a person I will photograph is look at them full face — nose directly at mine — and observe if their face is symmetrical. If it is I know full face and butterfly (a symmetrical pattern) will be most flattering. Why is butterfly more flattering for a naturally symmetrical face? Because putting the key light to the side always creates an asymmetrical lighting pattern which has the net effect on a symmetrical face of making it look lopsided, especially when the shadows on the face are dark.
If I see a face isn't naturally symmetrical that informs me that one of two strategies will help mask that fact:
1) If a full face pose is required, such as in a head shot for a business card, then I know I need to put my key light on the narrow side to create the illusion of size balance. Highlighting the smaller side makes it seem bigger perceptually. Shading the winder side caused the brain to pay less attention to it making it seem smaller. The net effect? A more balanced looking face. Finding the ideal balance is a matter of trying different amounts if fill to change the shadow tone. The darker the shadows the bigger the highlighted side will seem subconsciously when the viewer sees it.
2) If full face pose isn't required I'll use an oblique view with key at 45/45. In flat or broad light an oblique view on a dark background makes a face look wider than full face, but it also better reveals the natural 3D shape via the profiled far side and the way the nose sticks out and the light hits is and casts a shadow. What short lighting does that flat and broad lighting doesn't is highlight only the front "mask" of the face. The viewer's brain attracted by contrast to the highlight parts and tuning on the shaded side will perceive the face as being narrower and symmetrical. An oblique short-lit pose is a perceptual magic trick with two parts: hide the wider side with the camera angle, and then shine a spotlight on the front in a way that makes it seem symmetrical.
What happens when a photographer isn't aware consciously of this perceptual cause and effect?
If you have a subject with an perfectly symmetrical face, or are practicing lighting patterns on a mannequin head you'll never notice that cause and effect because it only occurs on faces which are naturally lopsided.
Symmetrical faces look the same if key light is on the right or the left. That's why beginners who practice patterns on mannequin heads usually encounter difficulty then trying the same patterns on the wife and kids who don't have such perfect faces. That's also true to some degree to following examples in lighting books where professional models are used. How come they are professional models? In part because they have naturally narrow and symmetrical faces which look balanced in any light.
When a face is asymmetrical and the key light is placed on the wide rather than the narrow side in a full face pose it will work to exaggerate the natural asymmetry rather than hide it. The same is true for oblique views. If the wider side of a asymmetrical face is put closest to the key light it will exaggerate the imbalance.
Will that make the lighting look "bad" or "unnatural"? No, because we see faces like that all the time. But once one becomes aware of this perceptual cause and effect and try shooting a lopsided face with the key light on one side or the other and compare the results you will likely conclude that ONE FLATTERS THE SUBJECT MORE.
Did Zucker explain it that way? No. He simply said of you see a face is lopsided put put the narrow side towards the window or off camera flash. I figured out the rest years later after reading scientific studies of how human perception works psychologically and that helped me understand why it works.
Aware of these things they inform the way I shoot portraits. My goal, even with candid "snap shots" is to try to find the most flattering combination of camera angle and face for that face . For example my wife's face is not symmetrical. Her face looks more balanced when seen obliquely than full and the asymmetry is obvious or hidden depending on which angle/patter I use.
It also influences C&C I provide to others. I can look at a photo and see if the face is naturally symmetrical, or not, in ways the photographer who took it wasn't consciously aware of. Often a photographer will post the same lopsided faces with various lighting patterns. Expressions being similar which will get the most favorable comments? The combinations of angle and lighting I describe above — noticing the face isn't even and putting the narrower side closest to the key light and putting the wider side in shadows.
Regulars know I seem to obsess about fill and tonal ranges, but that's due in large part from recognizing the control of fill gives the photographer in controlling how balanced the face looks. I can spot immediately seeing an asymmetrical face which side to place the key light for a 45/45 strategy to balance it, but I won't know the what the ideal balance of key:fill will be until I see how the camera renders the contrast of the lighting. Depending on the natural shape of the face and tone of the skin a 2:1, 3:1, or 4:1 ratio might wind up creating the best balance but I will not know until I try all three and see the results.
The need for fill is a technical one I learned shooting weddings. Weddings are one of the most technically challenging lighting scenarios because it is important in most (but not all) shots to have detail in the bride's dress, the faces, and the groom's and other black suits in the photo. For a head shot of a guy in a suit nobody will notice if the collar of the shirt is blown out, in fact it will often look better than way in a group shot. But you will notice if his bride is standing next to him and her dress is white blob.
Candid wedding shots are often taken in hotel ballrooms with high ceilings where there is no spill fill and in that situation your Fong Dong that works because it spills most of the light off the ceiling will not work. Exposing for the highlights in the dress will result in loss of detail in the shadows because a single flash with out any spilled fill creates even more contrast than outdoor lighting where there is always sky fill.
The decision to use fill or not is a simple one and related more to goals than technical considerations: is a full tonal range necessary in the photograph you are about to take? If you think not then there is no need to learn out to use it effectively to record a full range. If you know how to use it does than mean you must always use it? No, but you'll have the option to use it effective when needed.
Because my introduction to flash was shooting wedding photos in large hotel ballrooms where bouncing wasn't an option the need for fill was obvious and the technique taught to me by Zucker seemed very logical. The goal is detail in all the shadows the camera sees, because that's what is seen by eye (i.e. the natural baseline for comparison of "normal". Fill can't do that if off to the side creating shadows, so logically you want to put it where it doesn't create any shadows the camera lens sees. What part of that doesn't make sense to you?
In a two flash scenario indoors with no spill fill the off axis flash becomes the "key" light which creates the modeling. The role of the fill in that scenario isn't to add additional modeling but simply to allow the camera to capture detail in the shadow the key light modeling creates.
Fill is the foundation that lifts everything the camera sees just to the point detail is recorded in the shadows at whatever f/stop and ISO is being used. Key overlaps and creates the modeling. It can be raise to a point where the white dress retains its detail and faces will also be rendered normally. The net result is a full range of detail as seen by eye. It will look normal per that baseline of human vision because our eyes adapt to show us a full range with "normal" looking faces.
While that might seem creatively limiting to some, the simple fact is that when fill is moved off axis an shadows it creates are seen in those spots it will not be performing its primary task of putting detail in the shadows. In a situation like a bride and groom shot when the fill is shaded there will be no detail where key and fill shadows cross. That's why lights at opposite 45° angles from both sides isn't a good strategy. The highlights will be very even with that strategy but there will be no detail in many of the shadows on the faces and dark clothing when compared to the same 45° key light angle with centered fill.
Is there a rule you must always keep fill centered? No, but there also isn't one that says you should never center it either. The only way to decide which works better is to try both and evaluate the results.
None of what I suggest here is "rule" based. It is based on observation of the angle of natural light during different times of day and how different orientation of faces into that light makes them appear naturally 3D in 2D photographs. In like manner the advice on camera angles from which to view the suggested naturally flattering lighting are base on observation of all possible angles and deciding for yourself which look most balanced and natural, if those things matter to you.
The fill? Sooner or later you will realize you are controlling key light and exposure with a singular goal, to make the highlights on the face a similar "normal" looking tone all the time. Highlight tone is a constant in all lighting ratios.
The natural sun:sky ratio is three stops different, a harsh 8:1 ratio. Our eye and brain have evolved to make that ratio seem "normal". Our cameras haven't. The reason supplemental fill is needed is because it is often necessary to make natural light appear "normal" to fit the range of contrast the camera can capture. The technical criteria for when it is needed is whether the scene contrast lit naturally or with "key" flash exceeds sensor range.
There are no artistic/creative criteria for exposure and use of fill other than deciding whether or not a full range of tone is needed to create the look in the photo you envision in your imagination — your eyes and brain will perceive a full range most of the time (what looks normal) but normal is pretty boring because we see it all the time and other than normal is more creative because it makes the viewer see things in a different light, quite literally.
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