While there are entire books devoted to the subject of flash photography, this lecture also covers others types of introduced light.
Why do we need to introduce light?
Most importantly, light is all we have – without light there is no photograph. And sometimes the subject we want to image is not lighted, from natural sources, the way it needs to be to make the photo. Therefore, we need to introduce other light sources. Here’s an example of sunflowers and bees:
There are colourful sunflowers and bees, but the dark sky sucks the light away so that the bees are almost invisible and the sunflowers don’t dominate the way one would want. By introducing artificial light, in the way of Fill Flash (about which more lateer), and slowing the shutter speed, the desired photo can be captured:
Not all artificial light has to come from a flash, however. For example, a bedside lamp with a lampshade to diffuse and soften the light, can be a wonderful source of warm light (use a tripod and a slow shutter speed):
There were more photos shown, taken using the light from a bedside lamp.
One can also alter the White Balance if the tungsten light appears too yellow and the ISO if the subject demands a faster shutter speed (“work the scene to get it right” is a constant refrain throughout this lecture).
Other sources of introduced light are firelight or low sunlight deflected in various ways. Joel also showed examples of photos taken using light from automobile rear tail-lights or backup lights – in other words, take advantage of unusual light sources:
Continuous light sources are those for which the light stays on for as long as one wants, like flashlights, spotlights, lamps and so forth. They can be bought very cheaply and yet have spectacular effects (e.g. light painting). Joel gave an example of a photo captured using a cheap spotlight powered by an automobile’s cigarette lighter:
Another easily achieved type of introduced light is that which comes from a reflecting surface. It can be an inexpensive flexible reflector, a t-shirt, a coloured board, a cloth – anything which can be used to reflect direct harsh light, thereby softening it and potentially colouring it as well.
This led to Tip 2:
Flash for cameras was invented by Harold “Doc” Edgerton, a fellow Nebraskan:
Flash is a discontinuous source of light, typically a strobe light. A caution: flash can really ruin a photo, so it has to be used with care and understanding, which means “Chimp, Chimp, Chimp.” But flash can also overcome a bright background and pull a foreground subject out of the shadows.
Light from flash is cooler in colour, tending towards the blue end of the spectrum. When used correctly, however, fill flash can really solve lighting problems. To demonstrate, Joel went out into the field, to the Raptor Recovery Center, to photograph an owl. In the following series of images, Joel uses different techniques to move towards the “look” he wants:
In the above photo, Joel has removed the flash unit from the shoe position and attached it by a sync cord (there are also wireless flash units). Now he can light the owl from a direction other than straight on; however, the light is still harsh. Time to introduce a simple diffuser – a tissue wrapped over the face of the flash unit.
Notice how the light has been softened by this simple technique. At this point Joel introduced the softbox (seen in earlier lectures):
The softbox gives a better diffusion, softening the light from the flash even more. Getting the softbox as close to the subject as possible also softens the light. Move the softbox around so as to light the subject from different directions and angles; examine the results (Chimp, Chimp, Chimp – aka CCC).
Finally, take lots of shots (digital costs nothing!): Shoot-Chimp-Adjust-Repeat – as many as necessary.
Out of this field session came a number of tips:
Joel typically dials down his flash by 2/3 to a full stop (this assumes that your flash unit allows this kind of adjustment).
Flash does not have to be limited to indoor use, as we’ve seen. Use flash outdoors to light areas that would otherwise be in shadow. This led to another field trip, one in which two models were to be photographed while in shadow but against an ambient lit bright background.
The challenge is to work the scene to reverse the lighting situation (subjects lit, background subdued). The approach is to use flash within the softbox and to reduce the exposure length so as to darken the background. By adjusting flash strength, softbox distance to subjects, angle of softbox light, and shutter speed, one can move towards the desired image:
Move the softbox around to get different light angles – overhead, underneath, Rembrandt, 3/4:
The camera flattens 3 dimensions into 2 dimensions. A good photographer always tries to add elements which will give visual clues of depth, such as trees receding into the background.
Another thing to remember is that flash falls off very quickly so it is important that your subjects be roughly in the same distance plane – subjects deep in the image will not be light (although that may be an effect that you want to exploit). Of course, you can always play with changing the shutter speed and ISO.
Keep working the scene:
A point to note: during the above photo session, Joel, a published National Geographic photographer, took at least 20 photographs as he worked the scene.
One can also use flash to freeze action:
One can also “drag the shutter” by using longer shutter speeds or introducing other flashes or sources of light (think flashlights and light painting).
How slow should the shutter be set? You can’t answer that without “working the scene and situation”. Try lots of different adjustments and CCC!
This lecture’s assignment:
We now have been told about light in its various forms, we’ve learned about camera settings (exposure length or shutter speed, aperture, ISO, depth of field etc – all the basic technical stuff). Do the previous assignments (look back at earlier posts to be reminded) again and again, until you have a firm grasp on the use of the camera and the exploitation of light.
Next up the creative side: Composition.