Lesson 7 Composition part 2

Then next compositional trick, if your audience is finding the rule of thirds too subtle, is using converging line. This is the photographer’s way of pointing to the important part, and basically saying

“This is the bit I want you to look at, stupid!”



This works very well on landscapes giving very strong images which end up with a very graphic feel. The converging lines can be made up of anything from paths to roads or lakesides to streams, even man made structures like the lock gate in this picture ( a more subtle trick in this shot is the fact that the girl is looking at the point of interest, most people will look at what she is looking at).



Couple this technique with the rule of thirds and you can make sure people look at your image the way you want them to.



Going along the same theme is the trick of using just one line to lead people to the main point of interest, and the line does not have to be straight, in fact in this case a wavy line can make the image a lot more interesting.

Lesson 6 Composition

Over the past few lessons we have looked at the technical aspects of the camera, now we get to the more interesting part, taking pictures. The first bit to cover is composition; this is how you arrange the subject in the frame and the reason why you need to do that.

Your eye is a fantastic optical device, far better than any lens; it’s backed up by your brain, the most powerful computer on the planet. Working in combination they provide a unique window on the world, but a window that is molded by your interest in the subject in view. On the other hand your camera sees the scenes as light bouncing off objects, it gives no priority to any particular item in view, which means that the photograph has an objectivity all of its own. This is why when you see your photos they don’t match your memory of the event and why what looked like a great photo of your partner, now looks like there’s a tree growing out of their head.

This difference is one of the reasons why photography is so challenging as it makes you look at the world in totally different way, you will often hear it being referred to as “having a good eye for a photo”. Learning the basics of composition is the first step in developing this eye and the first compositional trick is the rule of thirds.




“The rule states that an image should be imagined as divided into nine equal parts by two equally-spaced horizontal lines and two equally-spaced vertical lines; and that important compositional elements (the leaf above) should be placed along these lines or their intersections (i call these hot spots)”

Once you start looking for this rule in use, you will see it every where, from films to TV, post cards to paintings. It’s the universal trick to making an image work, but why do you need to. Well as we have seen the camera does not give priority to any part of the image, so by putting the item that you deem important on a spot that will attract the most attention, you then start to replicate how your eye saw the image, making the finished photo a projection of what was in your mind when you took it.



In this shot the smallest item, the snowball, takes the attention as it sits on the junction of 2 dividing lines, with out this placement it would be lost as would the meaning of the picture. In real life, regardless of where it was, the snowball had my full attention.



The hot spot here is around where the hands join, here it just helps to reinforce the image.



With this image both the top of the paw and the cats face fall on hot spots, using the limited depth of focus helps highlight which hot spot is the important one

Lesson 5 - Film

The last part of the camera we need to cover is the bit that captures the image, be it film or the CCD. As we have seen in the past lesson the shutter and the aperture control the amount of light let in to the camera to create the correct exposure, but there is a third variable, the sensitivity of the film or CCD.

In the early days of photography the image collector (Glass slide or tin plate, coated with light sensitive chemical) was not very sensitive and exposures were measured in minutes. These long exposures lead to the staged formal portraits of the time as the people had to stand very still for a long amount of time.



As the technology has improved and film replace the other mediums, exposure times have tumbled to the fractions of a second we have today, giving us the ability to freeze fast moving subjects. But the increase in sensitivity comes at a price, a loss of quality and this applies to digital as well as film.

To get a correct exposure you need to regulate the amount of light hitting the image collector, you do this with the aperture and shutter, but the sensitivity of the image collector is what stipulates what amount of light you need. As a rule of thumb for both film and digital, the higher the quality the less sensitive the image collector, this sensitivity is expressed in the film or speed rating. This rating has carried over to digital from film so the term stays the same for both, so I will refer to it as film for simplicity.
The speed rating for film is given as ISO followed by a figure. Here’s the Wikipedia explanation;
“International Standard ISO 5800:1987 from the International Organization for Standardization (ISO) defines both an arithmetic scale and a logarithmic scale for measuring color-negative film speed. Related standards ISO 6:1993 and ISO 2240:2003 define scales for speeds of black-and-white negative film and color reversal film.
In the ISO arithmetic scale, which corresponds to the older ASA scale, doubling the speed of a film (that is, halving the amount of light that is necessary to expose the film) implies doubling the numeric value that designates the film speed. In the ISO logarithmic scale, which corresponds to the older DIN scale, doubling the speed of a film implies adding 3° to the numeric value that designates the film speed. For example, a film rated ISO 200/24° is twice as sensitive as a film rated ISO 100/21°.”
So ISO 100 is slower than ISO 200, but gives a better quality image, but what does this mean in real life. Say you are taking a landscape picture in bright daylight; ISO 100 will be great, as the camera will have loads of light to play with giving you access to a wide range of shutter and aperture settings. But take away a lot of the light, say a very dull day, and you will find that the range of settings that will give a correct exposure will diminish, limiting your creative control. But by increasing the film speed you effectively increase the strength or amount of light giving back the options you had lost, at the cost of image quality.

( For the full story behind this image see my post on 365 to 42 on the 02/03/09)

It’s this balance that will decide your choice, can the loss of quality be off set by the need for extra settings. For example; will the shutter speed be too low, giving camera shake to the whole image, totally ruining it, if so does the slight loss of quality but a sharp image off set this?
The real question is, how much quality is lost, this is down to you and your use for the image, ISO 100 is great but if you only look at the images on screen or in normal sized photos it is very unlikely you will notice the difference between 100 and 400, you are much more likely to see camera shake if you shoot too slow. Shooting on film you have to make the choice one film at a time, on digital you can change the setting for each shot. Even if your usage fits the above example, I would always try to keep the quality high as possible as you never known when you may take a masterpiece that you will want to print as large as it will go.

Lesson 4 - Aperture and Shutter

The Aperture and the Shutter are the yin and yang of photography, these 2 regulate the exposure and work together to affect the total image, and understanding their effect will take you along way down the road of mastering photography.

Aperture, if you look back to lesson one this is the opening that the light come through. On a camera it is normally a set of metal leaves that close in from the out side to leave a small round hole in the centre of the field of view. The wider the hole the more light can get in, if you ever hear of someone shooting wide open, this means that the aperture was at its widest. The wider the aperture the lower the number, so 1.8 is wider than 4.5, these numbers can also be seen on the lens, giving an indication of its speed, a low aperture lens is a faster one, due to the fact that wide open it lets in more light making for a quicker exposure. Due to technical restrictions, the faster lenses cost more to make, so a low aperture on a lens is also an indication of quality.

The Shutter is a metal curtain that opens and closes, very fast at times, to let a measured amount of light into the camera. The very first shutters were just lens caps that you removed for a set amount of time, say about 30 seconds, this was due to the time it took the light to effect the old types of film. Today’s shutters can move so fast that they only let in light for 8000th of a second and can be set to a wide rang of time, even up to multiple minutes.

The correct exposure for your image will be a combination of an aperture and a shutter speed, but if you move one and then move the other to compensate you will still get the correct exposure, but with 2 different settings. This yin and yang will continue until one or the other cannot make a corresponding move, giving you 10 or 20 different combinations of setting for the same exposure. Although the exposure in each case will be the same, the pictures will be affected in different ways; it is these differences that will govern your selection of aperture and shutter combination.



Aperture’s main effect is in the amount of natural sharpness it brings to the image, a smaller aperture will give you a sharper image. Now I say natural sharpness, as all cameras focus the light through a lens before it reaches the aperture. Left wide open the image taken just using the lens to focus will have a very narrow band of sharp image, think of a portrait with a blurred background. With the aperture closed down, that same shot will benefit from the sharpening from the aperture and have a detailed background. As we known the smaller the aperture the less light gets in so we need a longer shutter speed to get the right exposure.



The shutters effect on the image is mainly the way it effects movement. Take a picture of a bowl of fruit, this is not going to be moving, so how ever long the shutter is open the image will not change, but take a picture of a jet flying past and in a second it will have come and gone. By taking the picture at a fast shutter speed the amount of time the image is exposed, gives the jet no time to move across the CCD or film, leaving you with a sharper image as it will have no movement blur. The shutter also effects camera movement, as unless you have the camera on a tripod it will be moving by a small amount all the time, this is called camera shake. A faster shutter speed will also stop this from showing, a rule of thumb for hand holding a camera is a shutter speed to match the length of lens, so a 50mm lens need a minimum shutter speed of 50th of a second and a 300mm lens one of 300th of a second.

Put these 2 together and you get to the heart of camera settings, a trade off between speed of shutter and depth of focus, the auto setting on the camera will try to balance these two, giving a middle of the range shutter speed and aperture. A sports setting will try to pick the fastest shutter speed, to freeze the action, the landscape setting will try to pick the smallest aperture to give the greatest amount of sharpness in the image, and both will limit the selection based on the settings that give the correct exposure.



In most instances you will stick to these guidelines, but you could do the opposite, use a slow shutter speed on a fast subject to inject some movement into the image or a wide open aperture on a landscape to make only one item stand out as sharp. This can be done on a camera with only a limited number of settings if you pick the wrong one for the subject, as the camera will not know what it is taking and just do as its programmed.