Zoom It is a word of English origin that identifies the special telephoto lens that has a focal length that can be adjusted depending on the purpose of the user . This element, in other words, allows you to zoom in or out image according to its advance or retreat. The notion is not included in the dictionary of the Royal Spanish Academy (RAE) , which points to zum As the right term in our language.
As it is told, the origin of the zoom goes back to the first half of the XIX century , when the telescopes began to include mobile lenses that allowed to alter the focal length; at that time, it was necessary to refocus each time that value was changed.
The first zoom that allowed the focus to be maintained even when the focus distance changed was patented. Clile C. Allen in 1902 , while the first zoom lens that was produced on an industrial scale recently reached the market in 1932 .
The concept of zoom lens It refers to those tools that allow the photographer to manually vary the focal length and viewing angle. When choosing a camera, it is important to know the maximum and minimum distance of your lens, which is known as zoom factor ; it refers to the ratio that results when comparing the maximum and the lowest focal distance That can be achieved. Zoom 2x , for example, is a zoom in which the maximum focal length is twice greater than the minimum focal length. When the zoom factor is greater than 5x , people usually talk about superzoom .
He power zoom , on the other hand, it is a motorized zoom (the groups of lenses move automatically with the press of a button on the camera).
"Zoom" Finally, it is a song by soda Stereo made of Gustavo Cerati , which is part of the disk "Stereo Dream" .
Which is better, the optical or digital zoom?
Regarding the compact camerasIn the absence of interchangeable objectives they offer the possibility of using a optical zoom (which works through the movement of lenses) and the digital zoom (which cuts the margins and enlarges the central part of the image, using only a part of the sensor and reducing the quality). What does it mean?
The optical zoom is the approach that can be made towards the object analogically (by pressing a button), while digital is the one that comes into operation when reaching the maximum analog approach value. Generally the cameras show on the screen some lines that denote which of the two is being used.
To be clearer when using the digital zoom the machine captures the image and, through a installed software, make the approach or distance required; To do this you must invent those pixels that do not exist taking into account those you have captured. According to the complexity of this process and the quality of this tool, it will be the result obtained.
When purchasing a compact, it is quite important to take into account the value of both optical and digital zoom, since not being able to exchange goals, the zoom values will be invariable and will therefore determine the type of images that can be taken.
When asked which of the two is better, the answer is undoubtedly the optical because it is more true to reality; although if you learn to handle the digital correctly, incredible results can be obtained.