Posted on Friday, 6th April 2012 by Cee
A beginner might ask, “what is photography”?
The simplest answer is this, if photography is art then light is its paint. Your camera and lens combined is the paintbrush and you are the artist. Our eyes perceive every single object in our world because the available light shines on those objects, bounces off them, reaches our eyes and then the lens inside our eyes focuses that light onto our retina. This message is sent to brain to form a picture.
For the purpose of the rest of this discussion, consider that we are talking about natural light outdoors. I am not talking about indoor artificial light or outdoor street lighting. Just natural light from the sun. Although, it doesn’t really matter but just consider that you are out doors in natural light.
Light has three properties that are important to us as photographers. Let’s discuss them in more detail.
Property #1 : The Brightness of Light
When you hold your camera and frame a scene to take the picture, you’ll notice that there are different levels of brightness of the light in different areas of the scene. Think about it! There has to be, right? Because if everything in the scene was lit up with the same level of brightness, you’d see a single colour. This is actually impossible to achieve because we live in a three-dimensional world.
The Earth, the people on it and every other thing that you can see with your eyes are three-dimensional objects. So the light reaching and reflecting off different parts of those objects from one light source will never have the same level of brightness.
As photographers, this is good. This is what we want. The fact that the light reaching your camera’s sensor from different areas of the scene has varying levels of brightness is what generates a contrast in an image. Imagine for a second that there was no colour in this world. What other property of light would we then have to perceive and realise that the Earth is spherical and our world is three-dimensional? It would be the brightness of light. The difference in brightness comes from the inability of a single light source to reach all parts of a scene and then reflect off in the same direction because our world is three-dimensional. Objects, land, mountains, buildings, people, the planets in our solar system all have shape and this shape gives them form. The existence of form is what allows for a photograph to have contrast.
This is why I have spent two paragraphs talking about the brightness of light. To reveal to you, the concept of contrast. Contrast is the difference in brightness between the bright and dark areas in an image. The bright areas are known as the highlights, the dark areas are known as the shadows and the middle areas of brightness are known as the midtones.
We like contrast because it brings us right back to the realisation that we live in our extraordinary three-dimensional world. Without contrast, our images would look boring and flat. Images with more contrast have a striking impact.
If you take a look at the image on my homepage, you’ll notice in the modified version that there is a dramatic increase in contrast from the original image. This increase in contrast in my son’s hair, the lightening of his face and the whitening of the whites of his eyes with the darkening of the iris in my opinion, creates a much stronger image. It gives a clear idea of his character!
Here it is again.
To end this section on the brightness of light, from now on you should be aware of the term Subject Brightness Range (SBR). In this image above, I have generated additional contrast using software. But the whole point of talking about the brightness of light was to make you aware that when you take more and more pictures, you’ll encounter subjects with different ranges of brightness. Sometimes, the SBR can be so large that your digital camera will not be able to capture the details in the darkest and lightest ends of the scene that you are trying to shoot. To deal with such a problem, you have to take more than one picture with different camera settings and combine them using software, or by using filters.
Property #2 : The Direction of Light
The second property of light that we care about is the direction that the light is coming from. Direction is important because it brings into existence, the “elements of design” in our subject. What are elements of design? Line, shape, form, texture and pattern. These guys can own a separate page of their own but here, I’ll give you a brief outline of what they mean to us as photographers.
Line gives rise to shape because line has the ability to “define edges.” And when edges become defined, a shape is realised. When different shapes are brought together, they give rise to form in the third dimension. Something is formed – your subject’s face or a landscape scene is formed. Texture arises when shapes merge together without order and the surface of a formation is observed as uneven. The formation is inconsistent and therefore texturised. For example, have you ever owned a piece of fabric that isn’t smooth like silk, but has a rough… textured surface? Pattern is the repeated coexistence of shapes in a defined order.
The elements of design aren’t the only reason why we need to discuss direction. “Metering” is another reason. Metering is the process of determining what camera settings to use in order to make sure that you capture fully all the digital information from the highlights, to midtones through to the shadows. However, we’ll discuss metering in detail in a subsequent part of the course. I’ll discuss it here briefly.
The three main types of lighting we are concerned with are backlighting, frontlighting and sidelighting so let’s talk about these in a bit more detail.
Backlighting can produce some stunning images, but it can be difficult to work with in terms of metering.
Take a look at the photograph above – there is the sun and sky, and then there is the silhouetted foreground region at the front. How did I meter for this? I pointed the centre spot in my viewfinder to the orange/red region to the left of the sun at aperture of f/4 and the camera returned a shutter speed of 1/6400 seconds. This probably doesn’t mean much to you yet, but it will later. This resulted in a silhouetted foreground. If I wanted the detail to come out in the foreground, I would have had to point my centre spot to the foreground and take a meter reading there and take a second exposure at the new shutter speed for the foreground. This would have been a lot slower than 1/6400 since the foreground was quite dark. This is the difficulty of working with backlighting – because the source of light is behind the subject in the foreground, in the case of landscapes you will often have to take two exposures and combine them. For human subjects, you will have to use a flash or other light sources from the front unless your intention is to create a silhouette.
The point to note about backlighting is that it has a unique tendency to enhance the shape of the subjects it is lighting up from behind. How does it do this? The light defines the edges of the shape by diffracting at the edges. Diffraction is the process by which a wave will change direction when it comes into contact with an edge. Light is made up of little waves called photons. Have a look at the image above. Look at how the shapes of the hills in the distance have gained definition. The edges are clearly noticeable. Backlight tends to do this – the light diffracts around the edges and defines them clearly.
Homework: Place an object in front of a lamp in a room having minimised other ambient light sources. Take a picture of it with your digital camera and you should end up with something like the result below. The dark image of the Masai in front of the backlight source. The foregound however suffers – it doesn’t light up as well. To overcome this problem, photographers have to use an additional light source to fill up the foreground. If you hover over the dark image you’ll notice a second image where I’ve filled the front of the Masai with my flashgun.
To help you along with the homework, try to take the picture in “P” mode on your camera and see what results you get. I took this in manual “M” mode using the settings below the image. The curtains inside my room were shut and the only light source was the lamp behind Masai. Remember you are exposing for the backlighting source which means that you can settle for the Masai to be silhouetted and not have the light source blown out like a bright halo. Notice how the backlight source is well defined. If you find that the “P” mode result isn’t good enough follow, the instructions below. Get your camera manual to help you.
- Create similar conditions to mine in your room – curtains closed, lamp behind an object. Make sure object is thinner than light source like the Masai.
- Set your camera to Manual “M’ mode using the mode dial.
- Set your camera ISO to lowest possible value, perhaps ISO 100. Mine was set to ISO 50.
- Set your lens aperture to f/4 just like mine.
- Set your shutter speed to 1/60. 1/60 means “one 60th of a second”. On your LCD display however, it may just show up as the number “60″.
- Now take the shot.
- If the result is similar to mine, then you’re done. If the light source is blown out like a halo in comparison to mine, then you need to increase your shutter speed. Be careful, this means that your shutter will “open and close” faster which means a shutter speed of 1/80, 1/100 or 1/125 – bigger number! A shutter that “opens and closes” faster will let in less light making the backlight source more defined reducing a blown out halo effect.
So what have you learnt from this? You may sometimes want to photograph a human subject standing in front of a window or other source of backlight, but the subject’s face appears rather dark. Using a flash like I’ve done would resolve this problem, or tou may just want to leave it silhouetted. For landscapes where the foreground is much darker than the sky, you can use filter systems or simply take an exposure for the detail in the sky (in which the foregound would be dark) and an exposure for the foreground (in which the sky would be blown out lacking detail in its highlights). Then the two exposures can be combined digitally.
Frontlighting produces “flat” images which rarely evoke an emotional response. In this image, the sun was behind us at 6am in the morning. Not sure of its altitude, but it wasn’t directly above us just yet. Front-lit scenes will tell you a lot about what is going in the frame of the picture, but the mood and emotion are usually flat. How did I meter for this? Just pointed the centre spot at the grass and took the reading there. I used an aperture of f/11 this time which is smaller than f/4 because it bring more into focus from front-to-back.
In order for frontlighting to be an acceptable light source in terms of producing a good photograph, the subject must be interesting or elegant that the audience is drawn to it. Here is an image I made recently of Canary Wharf. When I shot the image at sunset, I knew it had great potential for a toned black and white image because the sun was shining directly on the buildings to the left which reflected the reds and the yellows very well. (A toned B&W image means it is a B&W image with a coloured tint.) So application of a red and yellow filter would have lightened these buildings up quite well in comparison to the ones on the right. To be fair the sun wasn’t directly behind me – it was behind and to the right so there is a bit of sidelighting going on here. You can hover over it to see the unchanged version. I really do think that the B&W version does it more justice than the original.
Homework: Do what I just did above. Shine light on your hand using your lamp from the right and take a picture of your hand. It should work well in “P” mode. Point the viewfinder’s centre spot at your hand and take the photo that way. Anyway, to nobody’s surprise… this is a side-lit subject. Sidelighting enhances edges and generates gradations of brightness on a subject bringing to it a confirmation that it’s three-dimensional. It creates an impact and a mood that frontlighting does not create. It brings contrast to a scene and has the effect of defining the subject through the sharp edges that it generates. Take a look at the gradations of brightness on my fingers which really sharpens up the edges. By bringing definition to the edges, sidelighting clearly emerges the elements of shape and form.
Property #3 : The Colourful Nature of Light
There is no doubt about it. White light from the sun is colourful so it’s important at this stage for you to grasp a basic understanding of colour. The best way for you to learn about colour is by means of the colour wheel so here’s one below.
There are four main points to consider about the colour in your photographs and you should always keep these in mind. When you are holding your camera, ready to take a picture, the colours in the scene at that time can give you a vision of what kind of image you want to create in the editing process. So let’s quickly go over the four points below.
Since the transitions in the wheel are a bit subtle, I thought I’d mention the colours in clockwise order – red, yellow, green, cyan, blue, magenta.
- Primary Colours: These are red, yellow and blue. The combination of two primary colours make the secondary colours. Or… a combination of sets of primary colours can make a wider range of colours. This is really for knowledge.
- Secondary Colours: These are orange, purple and green. Orange comes from red and yellow. Purple comes from blue and red. Green comes from blue and yellow. There are other combinations like I mentioned above, but these are the main ones you should know.
- Opposite Colours: Perhaps the most important to you as a photographer in terms of image manipulation is to first be aware that you should bear in mind the colours red, green and blue. (The RGB colour space is a dominant one in digital photography so it should be embraced quickly.) And then their exact opposite colours which are cyan, magenta and yellow. So how do opposite colours behave? Basically, in an opposite manner – reducing cyan, magenta and yellow enhances the reds, green and blues in your images and vice versa. When editing your images using software, you’ll work a lot with these six colours so please bear them in mind.
These are first three points to note about colour. The fourth is the:
- Mood of colour: Colours have moods that convey messages and emotions. A photographer is an artist… a designer who must have a sharp grasp of what type of moods and emotions emanate from a given colour.
Reds, oranges and yellows are colours of power. They convey a sense of warmth, but since they send a message of power… they can also be used effectively to convey heat and anger. These can be used creatively to enhance sunrises and sunsets.
Blues and greens are cold. They convey a sense of calm and relaxation, but since they are cold the mood that comes with them is often one of sadness, dark and gloomy. However, a blue sky with a mixture of Stratocumulus and Cumulus clouds on a summer day above the horizon is spectacular. We love blue skies as much as we love the warm, fiery sun but not at midday when the sun is blazing.
The light at midday is way too bright and brings with it a lot of haze and since everything is lit up well, the scenes are rather flat and lack contrast. The best light is at dawn before and a few minutes after sunrise and at dusk a few minutes before and after sunset. After sunset especially because as the sun dips under the horizon, and existence of clouds close to the horizon will cause the light from the sun to diffract splitting it up into lovely reds, oranges and yellows.
This is a very basic discussion of colour, but a good one at this stage. I’ll talk more about colour in the white balance section especially in terms of colour temperature, hue and saturation. The idea here was to introduce you to colour so that you are now more aware of it when taking photographs. It should be more obvious to you now than before. Seriously, I rarely paid attention to these colours when I first started out – it wasn’t so obvious in the beginning. It was all about clicking away without thought. Here’s a recent colourful panorama. Colour is wonderful and a major part of your artwork.
This brings us to the end of our discussion of light. Please bear in mind, the brightness, direction and the colour of light. These are fundamental concepts to master as a photographer. Learn them and enjoy them because they will bring joy to your photographic career.