Depth of field is the distance between the nearest and most distant points of the camera and arc in acceptable focus sharp in the image. The amount of this in the image is a function of the interaction of two factors:
1. The magnification of the image (with a focal data, determined by the distance from the lens of the object).
(2 Two) the color to which the lens is set.
It may vary by changing each factor or by changing the two.
Any given lens,
1 Reducing the distance from the camera of the object-for the purpose to increase the magnification image - will reduce the depth and vice versa;
2 Increase in the size of the opening of the lens will also provide low depth and vice versa.
It is a common mistake to say that wide angle, relatively short focal length lenses, will provide a greater depth of field than a normal focal length at the opening of the lens even lens. A similar error would be to say that long-focal will give less depth than the normal to the same bicolor. This would be true only if the distance from lens to object the same, have been preserved which would result in less image with the lens magnification wide-angle and more with a telephoto lens. But it is often the practice of distance from the lens of the object when focal lens is amended to insert the object in the image as desired. Depth of field is thus not a function of focal lens in itself; It is a function, such as the perspective of the image, the use of the lens.
Whenever a lens is focused on a topic there is only one only plan, from the subject at right angles to the axis of the lens that is truly emphasis, regardless of the setting of opening. This is known as the main focus. However, narrowing of the opening of the lens also shrink the angle of acceptance for the beam of light rays that will make up the image in a point on the sensor of the camera or a film. Each point of the image is actually a small circle, called the circle of confusion at least blur. This is shown more easily when the image is of a point light source, such as a star, on a background dark. No lens could effectively implement discussion as a single light point infinitely small. If the circle of confusion at least is very low (about 1/500th of an inch for a 35 mm camera lens), the image will be called sharp. With an angle very narrow acceptance for each batch of ray, there is a measurable distance along the axis where the circle of confusion less remain the diameter or smaller, so that the projected image will appear always sharp.
Control depth is very important for the last appearance of the photograph, f-parameters are not only arbitrary. Each choice of shutter and diaphragm setting combinations will represent therefore a compromise between the needs of the action - stopping what depth is required.
There are three ways to determine if the depth of field in an image is sufficient for your object.
1. You can close the diaphragm (most single-lens reflex cameras allow for visualization of depth while some still digital single lens reflex cameras keep this function) just by observing the effect on the relevant parts of the image of frosted glass. If the image should be enlarged in printing, close the diaphragm of one or two additional parameters to allow the enlargement of the circles of confusion in the impression.
2. You can see the specific scales engraved on the frame or body of most small cameras.
3. You can refer to tables of depth of field. With a given set of circumstances (such as the size of a subject, the degree of subsequent enlargement and the desired size of the circle of confusion at least on the final image), these tables can help you get the look you want for printing.
The first two methods are usually sufficient, the use of tables is usually only necessary when you use the film photography as with digital photography, you can always change the parameter accordingly after each take.
Learn more about photography advice and the camera to take pictures. Discover the basic camera photograph for more information.
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