Digital Camera Settings Explained
Digital Camera Settings can be set to do virtually everything automatically. This, of course, applies to the most important function a camera can perform: correct exposure.
However, making use of the options provided by the camera will help to enhance your results and, certainly, help to make your use of the camera much more interesting.
Many digital cameras provide an Exposure Mode Dial offering the following choices:
EXPOSURE MODE DIAL
P (Program): Allows photos to be taken automatically without your having to worry about the exposure settings.
A (Aperture Priority): You set the aperture you want and the camera chooses the appropriate shutter speed. (More details about this later.)
S (Shutter Speed Priority): You set the shutter speed you want and the camera chooses the appropriate aperture. (More details later.)
M (Manual Operation): You are able to choose both the aperture and shutter speed giving you full control.
Those are the most basic modes provided by many digital cameras.
As you can see, you can start right away without any prior knowledge, just by setting the exposure mode dial to P.
As well as an exposure mode dial there is usually a Function Dial. I will describe the three most important functions.
Drive: There are several drive modes under which a digital camera can operate. The most important is: Single Frame Advance. Just make sure that your camera is set to this function until you feel ready or inclined to experiment with others. Any other functions available will be fully explained in your manual.
White Balance (WB): This can be very useful enabling the camera to be set in accordance with the lighting conditions at the time. As usual, however, this can be set to automatic to save your having to worry about it.
ISO: This is the standard used to indicate camera sensitivity. More details on this later.
Let us now take time to look in more detail at some of the settings introduced.
APERTURE and SHUTTER SPEED
We need to take these two together as it is always a combination of the two that provides the exposure. If the combination is incorrect in the given lighting conditions then the exposure will also be incorrect.
In the P setting, of course, the camera makes the choice automatically. Why then, do we need to bother with the others? because there are some exceptions where we may want to take control.
There will be occasions, when you become more familiar with your camera, when you will need to decide whether depth-of-field (aperture) is more important or whether priority should be given to shutter speed. The camera cannot make that decision for you.
In photography aperture is defined by f numbers. The smaller the number eg. f/2 the wider the aperture and conversely the greater the number eg. f/11 the smaller the aperture.
Don’t get too worried by this for, most of the time, you can leave the decision to the camera. But, sometimes, for best results, you may need to intervene.
How do you decide when it is necessary to intervene and what criteria do you apply?
When you intervene the decision you are making is whether depth-of-field (aperture) or shutter speed is the most important setting. Let me start by explaining depth-of-field.
Quite simply the depth-of-field of any given lens at any given aperture is the amount of the picture in front of the lens which is in sharp focus.
Ask yourself if it is important for the whole picture to be in sharp focus, that is the near foreground and the far distance, perhaps in a landscape. Or are you, perhaps, taking a picture of a single flower in close-up where the background would be better out of focus in order to draw full attention to the principal subject, the flower?
For the landscape you would need to select a small aperture, (that is a high f number, perhaps f/11). But for the flower you would need a large aperture, perhaps f/2.
A small aperture, therefore, provides a long depth-of-field with everything in focus, and a large aperture say f/2 provides a short depth-of-field picking out the main subject to focus on at the expense of everything else.
If you have set the camera to A (aperture priority), the camera will select the reciprocal shutter speed to ensure a perfect exposure.
If you have set the camera to S (shutter priority), then the camera will select the reciprocal aperture to ensure a perfect exposure.
The choice of Shutter Priority is, perhaps, more obvious and would be dictated by the amount of movement in front of the lens, perhaps a sports meeting or children at play.
Each aperture has its reciprocal shutter speed for any particular lighting condition.
The important point is: the amount of light reaching the digital camera’s sensor is exactly the same with each setting the camera chooses. That can be described as reciprocity.
I hope that all that has not been too confusing and that it provides a clear explanation why it is sometimes necessary to choose either aperture priority A or shutter speed S depending on the picture you wish to capture.
In most cases you can, of course, choose P (Program) and let the camera do all the work!
WHITE BALANCE (WB)
This was touched on earlier when discussing the Function Dial, but now needs further explanation.
The concept is very simple; it just refers to the nature and strength of the light whether natural daylight or artificial light. The concept applies both to film cameras and digital cameras. With digital cameras, however, we have much more scope for dealing with it efficiently.
I’m sure you will have bought film on many occasions and you may have been asked if you wanted ‘daylight’ film or ‘tungsten’ film. Or perhaps it was just assumed that you wanted ‘daylight’ film unless otherwise requested.
Light intensity is measured in Kelvin and often referred to as colour temperature. Kelvin is a term similar to centigrade, but on a different scale and we don’t mention degrees.
Try to imagine a metal rod gradually being heated in a furnace. As the rod heats it would first become a dull red and then bright red eventually becoming white heat and even blue as the temperature increased.
A clear blue sky might measure between 10,000k and 18,000k whereas normal mid-day light may be about half that, say 5,500k. That would also be similar to electronic flash. Daylight film is able to cope with that difference.
But household tungsten lamps are about 2,800k and require a more sensitive film.
Now the great advantage of digital cameras is that they can cope with the whole range of lighting conditions. Many cameras have settings to cover a very wide range which can be adjusted as lighting conditions change.
Or, as is nearly always the case with digital cameras, just select Auto and the camera will adjust itself. However, selecting the appropriate setting, for instance, bright sunlight, clouds, shade, tungsten etc. is likely to prove much more accurate.
ISO (International Standards Organisation) This is the organization responsible for the ISO film speed system, combining the previous ASA and DIN systems.
You may remember buying 100, 200, 400 etc. film which, of course, relates to the speed, sensitivity, ISO of the film. Digital cameras allow you to set your own ISO and to change it as conditions change. Different cameras have options some going below 100 and as high as 1600 or 3200.
You may wonder if all those settings are really necessary. Before commenting further, let me urge a word of caution.
It is common knowledge among photographers that, with film, the slower the film the finer the grain and the faster the film, the courser the grain. Images taken with fast film, therefore are likely to look ‘grainy’, especially when enlarged.
It may not surprise you, therefore, to discover that the same applies with digital cameras. Instead of calling it ‘grain’, however, it is called ‘noise’.
If you set your camera to a high ISO rating there may be evidence of ‘noise’ in the final print, especially if it is enlarged.
There is, however, one very good reason for using a high ISO setting. If you are, perhaps, indoors, inside a church or other building where available light may be poor, then raising the ISO could enable you to take the picture without having to use a tripod. The camera becomes much more sensitive to the limited light so that the reciprocal shutter speed chosen by the camera may be sufficient to enable you to take the picture hand-held.
As a guide, 1/60 second should be satisfactory when holding the camera or even 1/30 second if you are very careful.
Although raising the ISO may create unwanted ‘noise’ on the final print you may consider it acceptable rather than not taking the picture at all.