Zooming in on the image is called zoom.
Zoom is a word of English origin that identifies a special telephoto lens that has a focal length that can be adjusted depending on the purpose of the person using it . This element, in other words, allows you to zoom in or out of the image depending on how far it moves forward or backward. The notion is not included in the dictionary of the Royal Spanish Academy (RAE) , which indicates zum as the appropriate term in our language.
According to legend, the origin of the zoom dates back to the first half of the 19th century , when telescopes began to include mobile lenses that allowed the focal length to be altered; back then, it was necessary to refocus every time that value was changed.
The first zoom that allowed focus to be maintained even when the focus distance was modified was patented by Clile C. Allen in 1902 , while the first zoom lens that was produced on an industrial scale only reached the market in 1932 .
Zoom lens and power zoom
The concept of a zoom lens refers to those tools that allow the photographer to manually vary the focal length and angle of view. When choosing a camera it is important to know the maximum and minimum distance of its lens, which is known as the zoom factor ; It refers to the quotient that results from comparing the maximum and lowest focal length that can be achieved. The 2x zoom, for example, is a zoom in which the maximum focal length is twice the minimum focal length. When the zoom factor is greater than 5x , it is usually referred to as superzoom .
The power zoom , on the other hand, is a motorized zoom (the lens groups move automatically by simply pressing a button on the camera).
A special telephoto lens with an adjustable focal length is called a zoom.
Optical vs. digital
Regarding compact cameras , in the absence of interchangeable lenses they offer the possibility of using an optical zoom (which works through the movement of lenses) and digital zoom (which cuts the margins and enlarges the central part of the image, using only part of the sensor and reducing quality). What does it mean?
Optical zoom is the zoom that can be made towards the object in an analog way (by pressing a button), while digital zoom is the one that comes into operation when the maximum analog zoom value is reached. Generally, cameras show lines on the screen that denote which of the two is being used.
To be clearer, when using the digital zoom, the machine captures the image and, through installed software , zooms in or out as required; To do this, you must invent those pixels that do not exist taking into account those you have captured. Depending on the complexity of this process and the quality of this tool, the result obtained will be.
Other zoom considerations
When purchasing a compact camera, it is quite important to take into account the value of its optical and digital zoom, since by not being able to exchange lenses , the zoom values will be invariable and, therefore, will determine the type of images that can be taken. .
When asked which of the two is better, the answer is, without a doubt, the optical one because it is more faithful to reality ; Although if you learn to handle digital correctly, you can obtain incredible results.
Title of a song
“Zoom” , finally, is a song by Soda Stereo .
This song was composed by Gustavo Cerati and is part of the album “Sueño Stereo” .