.Have you seen a portrait picture and the main subject is perfectly in focus while the background is blurry? That’s depth of field at work.
Today I will use the KISS principle to explain the depth of field. This was taught to me by the great professor that helped a lot at university.
Depth of field – is simply the amount of a picture that’s in focus. This is easily achievable by most SLRs in AUTO FOCUS mode. We want to learn the technique to achieve this all by ourselves. In order to understand this we need to know about aperture and how this affects the depth of field. It’s directly proportional to distance i.e. a subject at a greater distance will have greater depth of field than a close-up subject. Therefore, you need not worry as much about a distant subject being out of focus.
Size of Aperture
While changing the aperture (f-stop) will not have a striking effect on the depth of field for a distant subject or a wide angle (short focal length) lens, it can make a great deal of difference in a close-up or a photo taken using a telephoto or zoom lens.
A wider aperture (smaller f-stop number) will result in a shallower depth of field. You can use this to keep either the foreground or background out of focus while maintaining the subject in focus. When changing the aperture setting, you will need to also adjust the shutter to maintain the correct exposure.
So if you want to keep as much details sharp in a picturyoung would be best to set the smallest aperture as possible – preferably f/16, or even f/22 if your lens offers it
However, if you want to concentrate attention on just one part of the scene, and throw the rest out-of-focus, it would be best to select a larger aperture. Exactly how large this can be depends on the maximum aperture of the lens you’re using. On a 50mm standard lens it will be f/1.7, f/1.8 or f/2, but on a standard zoom it will typically be f/3.5 or f/4.5.
For general picture-taking, when you want most of the picture to be in focus, you might want to set a middling aperture of around f/8 to f/11.
For example, if you attach a WIDE ANGLE LENS, you are more likely to have an extensive depth of field which will be really easy to keep everything in focus. Wide angle of view = greater depth of field.
With a TELEPHOTO LENS, the view is m.uch more restricted so the longer the foal length = restricted zone of sharpness.
Relationship between camera-to-subject teaches that the CLOSER you are to your subject, your depth of field becomes LIMITED.
Examples O Depth of Field
If you have an questions you know where to find me. Have a fabulous weekend guys!!!!!!!!