Lighting 102: Unit 1.1 - Position (Angle)
We live in a world of off-axis light. The sun does not stay right behind us. Our lighting fixtures at home illuminate us from above and other various angles. And we are constantly exposed to imagery - both still and moving - that makes use of very sophisticated off-camera lighting techniques.
Yet so many photographers, when they take the time to compose and illuminate their photos, settle for the bland, flat, on-axis (i.e., on-camera) light. Because that is the path of least resistance.
The biggest failing of on-camera flash is that the light, which comes from a point very near to the camera's optical axis, does not have the ability to reveal the three-dimensional quality of the subject.
Granted, most flashes can be tilted to bounce the light off of walls or ceilings while still attached to the camera. But those are very limited choices out of a wide variety of lighting angles available to the off-camera lighting designer.
For the purposes of this discussion we'll think in terms of only hard, bare light from a typical electronic flash. (No worries, we'll be softening it up soon.) But the idea at this point is not to create flattering light for a subject, but to explore the way off-axis light reveals and defines an object.
The first thing that you have to consider when visualizing (or pre-visualizing) the effects of off-axis light is to remember that there are two points of view in play. The first is that of your camera, which defines what you will be able to see in the photograph. But just as important is the second, which is the point of view of your primary light source.
What your light can see will define what is lit in your photo. If your light cannot see it, it will not be directly lit.
The ability to visualize the difference between these two points of view is the key to understanding how changing your light position will alter the way your subject appears.
Look, You Already Know This Stuff.
As we start this process, it is important to begin to merge the way you think about continuous light and the way you think about flash. I really cannot overstate the importance of learning to think of strobe the same way you think of continuous light.
Why? Because you are already a seasoned pro at dealing with continuous light. You experience it and react to it all of the time. You see a shadow and instinctively know where the light came from. You know by the edges of the shadow whether the light was hard or soft.
If you can learn to think about flash as a very bright, continuous light source, you will be able to make use of all of your experience with light that you have been subconsciously building for your entire life. Thinking of a flash as a very bright continuous light source is not so easy for some people. But it will get you past the math-anxiety-type fears you may have about learning how to light.
Heck, even a little mouse munching on lunch in a field knows it had better haul butt when it is suddenly darkened by a shadow. It very well could be an approaching hawk. And the mouse likely knows which way to run when the shadow appears if it has a situational awareness of the lighting environment it is in.
Here is simple exercise that will improve your light visualization skills. Stand in front of a mirror, holding a (lit) table lamp in one hand. Move the light around so that it falls on your face from a series of angles and observe the results.
Yeah, you might feel (and look) a little goofy doing this. Oh, and you might want to have a good response ready for when your significant other pops in and gives you one off those "What the...?" looks, too. But I can vouch for the fact that it works very efficiently to train your eye to light.
Reverse Engineer Photos to Sharpen Your Perception of Light
Let's see what we can tell about the light in this photo just from studying the shadow:
1. Well, right off of the bat we know that the light is coming from camera right, because the shadow goes to camera left. (Don't get cocky. The mouse could have figured that out.)
2. We know the light is hard because the shadow edge is hard. (We're not there yet, but you know that info all the same.)
3. We know the light is slightly higher than the subject because the shadow goes slightly down.
4. We know the light is fairly close to side light (i.e., close to the wall) because of the length of the shadow.
(Note that there is a very dim secondary shadow at camera right. This is coming from the ambient light, which is not totally overpowered.)
It's just a dumb, quick little exercise. But the more you make it a habit to look at photos with an eye toward analyzing the light, the easier it becomes to create any effect you are looking for with your own light.
Here's a little home experiment to try without even making a photo. Position a household lamp so that it illuminates an object. Look at the object from the position of the lamp. See what the lamp sees. Now move away from the lamp and study the changes in your subject as the lamp reveals the object in relief while you move your point of reference further away from the axis of the light source.
Compare the lit portion of the object (as you move away from the lamp) with what you were able to see of the object from the position of the lamp. That's the first step to pre-visualizing light.
Do this kind of exercise enough, and you'll be able to know exactly how a subject will look when lit from any direction before you ever position your light. Better yet, when you pre-visualize a photo you'll know at what angle to position your light to get the effect that you want.
There are actually two variables to consider when deciding where to position a light. The first is at what angle to light your object. The second is at what distance to light your subject. Each variable offers a different form of control for a photographer to exploit.
Let's Try it with Some Live Ammo
For the first little shooting exercise, we'll be dealing only with angular position of the light. This experiment is going to be so simple that many of you will not even want to do it. But I really hope that you do.
Take a person or object (in my case, Combat Camera photog Jason Robertson, from the DINFOS workshop earlier this month) and shoot it/him/her with the light very near the camera axis. You can even stick the flash directly fired on camera for the first shot. You should have a wall behind the subject (with a few feet of separation between the two) as a reference for any shadows.
As for exposure, try this method as a way to start to learn to light without a flash meter. Shoot in a normally lit, indoor room. Set your ASA on 200 and your camera at your normal max synch speed. For most of you, this will be somewhere between 1/125th and 1/500th. Set your aperture on f/5.6.
Start with your flash on manual at, say, 1/16th power, about five feet away from your subject. (If you keep the flash-to-subject distance the same as you change the angle, your exposure will not change.)
Now do a test shot. You subject will likely be a little too light or too dark. Adjust the aperture on your lens until the exposure looks right. If this seems clunky, understand that working this way will soon turn your brain into a built-in flash meter. With a little experience, your first tries will get closer and closer and exposure adjustments will be more and more minor.
Back to the exercise.
After adjusting for a good exposure for your on-camera light, move the flash around the subject and shoot it from a variety of lighting angles. For the example above, I just put up a straight-on and a 45-degree lit shot. But you'll want to play with it more than that. Experiment with some hard angles, in addition to the normal stuff. Look at the different ways in which your light reveals the subject. Again, keeping the distance constant will help keep your exposure constant, too.
Try a shot with the light at about 45 degrees to one side. Have your subject look directly into the camera. (Or have your inanimate object continue to be inanimate.) Now, keeping the subject looking in the same direction, walk over to your light and shoot the subject from the perspective of the light.
Compare the two photos, noting what you see from the position of the light with what portion of the subject was lit in the straight-on photo when the light was hitting it at a 45-degree angle. This may seem like rote, boring stuff. But the goal is to learn to light in a more intuitive manner. And observing your subject from the position of your light source is a great first step in that direction.
There is no need to stick these in the Strobist Flickr pool, but you are welcome to do so if you want. The important thing is to start actually doing this stuff and to learn to use the tagging process. Then we can easily tag, group and view the more challenging assignments later.
When uploading this exercise to Flickr, your photos should have the following tags:
• lighting102 (note that there are no embedded spaces)
If you do that, everyone will be able to easily find them with by clicking here. We'll be talking about this exercise next Monday (June 25th) and moving on to discussion of Unit 1.2 - Position (Distance).
Questions, answers, etc: Please use the discussion-specific Flickr thread for further discussion.
Related Archive Pages:
L101 See the Flash
L101 Be the Flash
L101 Reverse Engineering Light
Bloggers/Vloggers: If you are blogging your exercises/assignments online, or posting videos about the process, you can include your efforts in the Technorati Trackbacks by linking to the permalink of this post.
NEXT: Lighting 102, 1.2 - Position | Distance
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