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What are the advantages of a closed shutter in the focal plane?

What this name implies is that the closed shutter in the focal plane is located (actually in front of and close to the true plane of focus) (Fig. 22). It is not affected by changing the lens and does not hinder reflective vision. The main reason for installing this type of shutter is that it allows changing lenses without the need for another shutter to prevent blurring on the film. Since the timing mechanism only has to set the delay period between the first and second curtain, faster speeds can be precisely controlled (1/1000 of a second is normal, 1/2000 of a second is normal) and remain true for longer periods.

What are the disadvantages of a closed shutter in the focal plane? . At short shutter speeds the film is effectively exposed in the form of a moving slit. This takes anything from 1/125 to 1/30 of a second (in some roll film models) for the film to be cut. Any part of an object that moves during this period can be recorded as a distorted shape. This explains the image of racing dump cars taken during the turn of the century with the slower moving shutters in the focal plane. The worst problem caused by exposure to light through the longitudinal slit is that the electronic cannot be used at any speed shorter than the period of time it takes for the shutter to block the light in Transition through all the film The reason why flashes are known to shutter shutters in the focal plane is that they form
It consists of a pair of horizontally moving rubberized fabric screens. In modern times, there has been a great development in the manufacture of all-metal types that move vertically. In any case, this idea is not entirely new, because the Contax camera, which was popular before the war, had a metal shutter that moved vertically.

When taking pictures using an electronic flash (with an instantaneous discharge), the entire film must be exposed to light at one time, and thus the speeds at which the flash can be used are determined - and are often located within a range of 1/30 - 1/60 of a second for shutters with Horizontal movement along the film. As for the vertically moving types that travel a distance shorter than the height of the film, the maximum shutter speed can range from 1/60 - 1/90 of a second, and in some cameras the speed may reach 1/125 of a second.

What is the normal range for shutter speeds?

Traditionally, cameras have been equipped with shutters that give exposure times from one second to 1/500th of a series of a second.

During a certain stage, the exposure times were usually arranged as follows: 1/2, 1, 610/1, 1/60, 1/01, 1/10, 1/0.1" 1/200, 1/500 seconds.

Nowadays, the order has generally become as follows: 1/15, 1/60, 1/1/125, 1/10/8, 1/2, 1/1500 seconds.

This exactly equilibrates the exposure time at each .

Most cameras with shutters in the focal plane are characterized by shorter speeds, which are 1/1000 and often 1/2000 of a second. Some high-quality cameras always allow longer exposure times (lasting up to 10 or 15 seconds). Now, electronic shutter speed timing allows for long shutter speeds to be provided in a wide range of cameras. This is often available with automatic exposure time control.

Why are most mirrorless cameras equipped with leaf shutters, while most SLR cameras have shutters in the focal plane?

Through the Lens The principles of the SLR system require that the image intended for viewing and focusing be equipped with passing light. . This requires that the shutter be installed behind the lens to protect the film. There is a system in which two shutters are used, one to expose the image to the other light, to protect the film between exposures. However, this requires complex and expensive interlocking mechanisms, with a prolonged delay period between pressing the shutter-release mechanism and the exposed film. It also makes individual lenses heavier and more expensive to be subject to contraindications in the event that the shutter requires maintenance and service. Another disadvantage of lenses with an internal shutter is limited choice among them by independent manufacturers. For this reason it is better and cheaper in the long run to install a shutter in the focal plane with

Mirrorless cameras, especially those without an interchangeable lens feature, have no such restrictions. In this case, the detachable shutter with an interstitial lens is one of the most economical issues, and electronically controlled types are now available with maximum shutter speeds.