Distance, Focus, Depth of Field
Distance is one thing you will always have to calculate with. It determines a lot of things when you take a picture. For this session, let's completely forget that shutter speed as it is exists. Here are some examples:
- If you take a picture from a short distance of a dark object, the aperture needs to be wide-open and the depth of field will decrease. This will create sort of an artistic effect (aka "bokeh": the subject will be in sharp focus but everything else in the background or outside a short distance will be blurred or washed away.
- If you take a picture in a bright day from a larger distance e.g.: 3-5 meters, your aperture will need to be quite a bit closed (or stopped down, e.g.: f/8 or f/11) thus creating a deeper depth of field. This means that almost everything - save for your finger that you left just in front of the lens - will be razor sharp.
As you have noticed the color (more like the brightness) of the object that you are taking a picture of heavily weights on how your depth of field will end up. This is because we did not touch our shutter speed or ISO setting. (With a film camera you would not be able to change ISO anyway.)
If you set your ISO to high (more sensitive) your aperture will not need to be open and you will be able to take a darker picture with larger depth of field. It's as simple as that. If you have a compact camera where you cannot touch aperture settings, you'll still probably be able to play with ISO to make some difference.
There is one thing you need to know about depth of field: in total it is controlled by 3 things:
- aperture
- distance to focused target
- focal length
You already know these three if you came through the pages in a straight order. If you did not, go back and read about these things.
Aperture: the larger your A opening is (which is a smaller value) the shallower the DOF is.
Distance: the closer you are to the target, the shallower the DOF is.
Focal length: the longer your lens (or the zoom focal length) is, the shallower the DOF is.
- If you take a picture from a short distance of a dark object, the aperture needs to be wide-open and the depth of field will decrease. This will create sort of an artistic effect (aka "bokeh": the subject will be in sharp focus but everything else in the background or outside a short distance will be blurred or washed away.
- If you take a picture in a bright day from a larger distance e.g.: 3-5 meters, your aperture will need to be quite a bit closed (or stopped down, e.g.: f/8 or f/11) thus creating a deeper depth of field. This means that almost everything - save for your finger that you left just in front of the lens - will be razor sharp.
As you have noticed the color (more like the brightness) of the object that you are taking a picture of heavily weights on how your depth of field will end up. This is because we did not touch our shutter speed or ISO setting. (With a film camera you would not be able to change ISO anyway.)
If you set your ISO to high (more sensitive) your aperture will not need to be open and you will be able to take a darker picture with larger depth of field. It's as simple as that. If you have a compact camera where you cannot touch aperture settings, you'll still probably be able to play with ISO to make some difference.
There is one thing you need to know about depth of field: in total it is controlled by 3 things:
- aperture
- distance to focused target
- focal length
You already know these three if you came through the pages in a straight order. If you did not, go back and read about these things.
Aperture: the larger your A opening is (which is a smaller value) the shallower the DOF is.
Distance: the closer you are to the target, the shallower the DOF is.
Focal length: the longer your lens (or the zoom focal length) is, the shallower the DOF is.