Lighting in Digital Photography
Positions of Light Source, Object and Camera
A good photo doesn’t need any change. A bad photo will never be good.
This article deals with very basic aspects of positions in digital photography only. It targets the amateurs and does not claim at all to exhaust the subject even at this level. Just it brings to the reader’s attention some basic aspects for making good pictures when shooting with digital camera. We hope this article will raise interest for comments within this site and for further reading on Internet and elsewhere.
Simply put, assuming that the object is not a light source such as lamp, there are three main elements in photography: light source, object and camera.
The light can come from different sources such as: (i)direct sun, (ii)cloudy sun, (iii)sunlight reflected by large objects or surfaces; (iv)incandescent bulb; (v)fluorescent lamp; (vi)lamps used to illuminate the streets, (vii)LED or (viii)speedlite or flash. Throughout this article we prefer to use speedlite instead of flash, to avoid confusion with flash memory. This enumeration of light sources is based on the color of each category. It will be a separate article about the color of light sources and its impact on colors of digital pictures.
There are two major aspects related to light in digital photography:
positions of the light source, of the object and of the camera, and
color of the light source.
This article covers only the positions aspect, summarized in Position schematics, with examples of portrait pictures.
Take note that this discussion about positions holds true for any color of the light source.
It is important to mention that the light source in all Position examples has small size, such as a bulb. For outdoor shooting, even the Sun is considered a small size white light source with parallel rays. If you look at the Sun through a strong absorption filter, it appears quite small comparing with a person or with a landscape size.
In all Position pictures, the transitions between light and shadow are sharp, which should be avoided for obtaining a pleasant portrait, unless the photographer takes advantage of shadows for highlighting some object features. Just compare any picture in Position examples with the picture in Diffused Sunlight example, where the picture was taken outdoor, in slightly cloudy sky.
Everybody wants to shoot nice pictures. This is not very difficult to do if the photographer pays attention to some common-sense aspects. In sunlight, the pictures are vivid with natural colors. For a good picture, the photographer must look carefully for smooth transitions from light to shadow on the object. In Diffused Sunlight example, the light from the Sun was scattered by clouds, which became an extended or broad light source, producing smooth shadows on the object. In the Diffused Sunlight example, you can easily depict the position of the Sun, but the picture is pleasant.
For indoor portraits, the shadow can be controlled better by using extended light sources such as softbox and studio light source as extended light sources. Below you see examples of both soft sources. The softbox make soft transitions between light and shadow on the object. The studio light source makes a light spot with soft boundaries on the object for highlighting a particular area.
Be aware of using studio lights: a softbox gives a single smooth shadow per object feature as you can see on the Smooth Shadows examples below; replacing the softbox with multiple studio lights might make multiple smooth shadows of the same feature of the object.
The picture at the left hand side was made using multiple softboxes and also several diffuse reflection panels. For the picture at the right hand side, the photographer used several sources with different colors making diffuse illumination at different angles, as it can be depicted easily.
The softbox can be used also for mitigating the shadows in outdoor shooting, as you can see below. The benefit is obvious.
Several light sources and accessories for diffused light illumination are shown below.
Here is an example of photo studio using softboxes.
Back light illumination is often encountered when shooting either indoor, or outdoor. When the object is back illuminated, the object side facing the photo camera is strongly shadowed by the object itself. Vast majority of digital cameras have an embedded speedlite. The embedded speedlite will illuminate the object side facing the camera, but will eventually introduce also shadows on the object, because its light is not scattered enough. It is a widespread perception, that the speedlite is used only when there is not enough light for reasonable shooting, either indoor or outdoor, usually indicated by camera. This is partially true. Some comments will clarify the issue.
If the photographer wants to do a quick shot for a reasonable quality picture, it is OK to use the speedlite in this way. The picture will have some shadows with sharp transitions, expected and accepted by the photographer. If the subject is a person or an animal looking straight at the camera during shooting, the eyes could have red spots or red eyes removable further by a multitude of means. Many cameras have the option for red eyes reduction. We suggest the use of the built-in speedlite as it is for object illumination only when you do not have a better choice.
More interesting is the situation when the photographer wants to shoot a good picture either indoor, or outdoor, using a standalone speedlite. This option is always better. All embedded speedlites illuminate the object straight, eventually producing shadows with sharp edges. Practically, there is no way of attaching any light diffuser to the embedded speedlite. The situation is totally different for the standalone speedlites, having available specially built accessories such as diffuser and softbox, as you can see in Speedlite, Softbox and Diffuser picture above. The speedlite diffuser gives very good diffused light, is easy to handle and to carry on top of the speedlite. For indoor shooting, it is better to direct the speedlite head toward the ceiling, for taking advantage of further light scattering by the ceiling. Do not worry abut underexposure. Good speedlites are strong enough and they have a dialogue with the camera through the hot shoe. The speedlite measures the back reflected light from the object, and the camera stops the speedlite lamp when the proper illumination was reached. Having attached either a diffuser or a softbox, the speedlite can be aimed to the object; no worries about shadows.
Just look at the example below to see the difference between the back light illuminated pictures shot without speedlite or flash and with speedlite.
Landscapes are illuminated either by sunlight, moonlight and sometimes by streetlights. These three main lighting categories are very different; therefore there will be different comments for each of them.
For landscapes shot in daylight, side lighting is preferable. In the example below, the shadows highlight some elements and give three dimensional aspect of the picture.
Top lighting might emphasize a certain area of the picture. In this way, the photographer could send a message to the viewer.
Front lighting gives a strong perception about depth; the shadows are very long. For this type of shooting, be aware that the direct sunlight may compromise the entire picture. The use of a graduated neutral density filter is a must.
Back lighting can produce astonishing pictures, too, when balancing properly the strong illuminated areas with some shadows.
Moonlight is very dim; therefore, the exposure times are long in nighttime shooting. Quality moonlight shooting requires a tripod, even when using high ISO speed such as ISO6400 and up. Low speed ISO100 or lower are suggested for revealing picture details and low noise, thus requiring tripod. Image sensor area should be as large as possible to collect as much light as possible, such as in digital SLR cameras Canon EOS Rebel T3i, Nikon D5100 and similar, or in full frame digital SLR cameras, such as Canon EOS 5D Mark III, Nikon D800 and similar. The lens should have small f/#, and the diaphragm should be as wide as possible. Lens focused at infinity gives the best results, with a large depth of field. If the picture include the Moon, pay attention to its move in the sky. Longer exposure times might elongate the moon, something you do not want to happen!
Be aware also of the noise (grains) in the image: higher ISO speed means more noise, but ISO100 or lower gives the best results. Shutter release is also very important: triggering the shutter should not move at all the camera.
Shooting streets in the night requires attention to the light from closer lamps, which may affect the shutter speed. As a rule of thumb for any nighttime shooting, take several shots of the same scene with different shutter speeds and focusing. Do not rely totally on the camera auto focus in this case; try manual focus, too. Later you will select the best picture.
You have below several examples of beautiful night pictures.
Obtaining good pictures in different illumination conditions is definitely related to photographer skills, which requires passion and experience.
Hopefully, this article is useful and triggers the attention on some light related aspects in digital photography.