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IRIS in the camera

Aperture in the camera - what is it?</a>

Aperture is one of the parts of the camera lens, it takes an important part in the "construction" of the image.

What it is, how it works and how it can be used, you need to know every photographer who discovers a wide range of shooting possibilities with manual settings.

What is the aperture and how does it work?

To understand how the diaphragm works, it is importantUnderstand how cameras generally convert the incoming light into an image. In order to better understand the principles of the camera, it is better to give an illustrative example.
Imagine an absolutely dark room in whichThere is a window with black glasses, through which light does not penetrate. If you open it a little, leaving a small gap, you will see a thin strip of light on the opposite wall. If you open the window completely, then the whole room will fill with light. In both cases, the window was opened, but the lighting characteristics are completely different. In the camera, the aperture plays the role of the window, and the role of the wall on which light enters is the matrix that fixes the image. The extent to which the diaphragm is widely opened determines many characteristics of a future photograph. Many, but not all, since the diaphragm is not the only element taking part in this.
What does the aperture look like? This damper is assembled from so-called "petals", which, rotating around the circumference, form holes of different diameters (see attached photo). Do you remember the analogy with the window? The size of the circular hole that forms the movable petals is similar to the width of the opening of the window. A diaphragm can consist of a different number of petals, and this also plays a role in the construction of the image.

How to use aperture

In the camera settings and on the markingThe aperture characteristics are indicated by the letter f with the numeric values ​​assigned to it, for example: f / 1.2 or f / 16. It is important to remember that here the inverse relationship is used, that is, the smaller the number, the greater the aperture opening (the "window" is wider). Thus, the value of f / 1.2 means that the aperture is wide and there are many light on the matrix, and f / 16 is small. When choosing a lens, it is important to pay attention to the marking f /. The lower its value (based on the standard f / 3.5), the better.
At the maximum open aperture on the matrixReceives a large amount of light. This allows you to take pictures in low light without the use of flash and long exposures. By the way, exposure is a time interval that determines the time during which the shutter of the camera remains open, letting light on the matrix. If you return to the analogy with the window, then this is the time during which you will keep it open.
In addition, the opening width of the diaphragm determinesDepth of field. If to explain simply, this is the number of subjects in the frame that are in focus and have clear, sharp edges. With a wide open diaphragm, their number will be small. Surely many saw portraits, on which a person is clearly captured, and the background is blurred. Or in focus is only a small detail of the subject, and everything around is blurred. In photography, this beautiful effect is called the "bokeh effect".
With maximally open apertures, you canSeek to focus on the smallest details, and all other light sources will be blurred in the image in multi-colored points of a circular shape. Now it's time to return to the diaphragm's petals. The more of them (in standard, inexpensive lenses they are, as a rule, five to seven), the more round the hole they form, and the softer will be the blurring.
In contrast to the widely open holes, coveredThe diaphragm provides a greater depth of field, that is, more objects will be in focus. This is widely used when shooting, when it is necessary to show all the details, for example, architectural, or landscape.
Also such aperture settings are neededUse when shooting at night with a tripod and long exposures. Not in low light, but at night, when the number of light sources is minimal. A narrow aperture allows you to take clear pictures without a "glare", which shows all the details.
Knowing the theory, it is important to experiment with differentDiaphragm values ​​by yourself. After seeing the difference in the pictures, you can learn to choose the right value for different conditions and always achieve excellent results.

IRIS in the camera Was last modified: May 23rd, 2017 By Vaunoavg
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