Aperture and shutter speeds affect your pictures
Aperture is the opening of the camera for the light to reach the digital sensor or the film. The aperture also determines the depth-of-field of your subject. The followings explain how the aperture affects your picture.
Big or large apertures (f1.4 to f.5.6)
These apertures contribute to the shadow depth-of-field of your subject.
This means that the area of sharp focus on you subject is very small in terms of depth. For example, you are taking three rows of people and you focus on the 1st row, the faces of those in 2nd and the 3rd rows will not be as sharp as the 1st row. These aperture settings can be useful when you want to isolate subject of your picture from the distracting surrounding which you want to throw them out of focus. You would use these settings mostly for taking portraits and close-up photography
Small apertures (f16 to f32)
Small apertures increase depth-of-field which means that the foreground and background of your picture are in focus if not sharply focus. This creates depth to your photograph drawing attention of your viewer to the whole picture. These settings usually apply to landscape photography.
Mid range apertures (f8-f11)
These settings are most common and are able to render sharp pictures for general applications.
Use high shutter speeds
A good rule to observe while taking pictures with the telephoto lens, that is to shoot at a shutter speed not less than 1/focal length, the faster the better. As an example, if you shoot using a 300 mm lens, you should shoot at a shutter speed of 1/300 or greater. The reason behind this is that as you magnify the image you are taking, you are also magnifying the effects of camera movement.
You can counteract this by shooting at a higher shutter speed or mounting you camera / lens on a tripod.
How to maximizing sharpness:
If possible, always use a low ASA film or a low ISO sensitivity, this will prevent the photo from being too grainy which affects the sharpness of your subject.
Some high end camera can set to higher ISO without making the picture too grainy, so you must know the optimal ISO setting you can go without introducing too much grains.
Observe the rule when using zoom lenses, always set your shutter speed higher than 1/focal length
Depending on your eyesight, if your eyesight is good, try to do manual focusing when shooting with wide open aperture like f2.8 to f3.5 so that out of focus will not occur due to recomposing when using auto-focusing.
When taking human or animal subjects, focus on the eye
Always use a tripod when taking low shutter speed shots. A heavy and firm tripod would be good but not always practical for walkabouts.
Never use the widest aperture of your lens for shooting say shooting f2.8 with a f2.8 zoom lens. Always shoot at 1 – 2 stop smaller than the specified limits (say f4 – f5.6 for a f2.8 lens). This is due to the construction of the lens and the glass elements involved.
Written by: David Tui
Author’s Website: http://photography.host56.com/
