what is aperture and focal length and depth of fileld

Gadgets have influenced mankind like never before, life without it feels difficult. As the days are passing technology is evolving and so the the gadget  i.e in earlier days gadgets like mobile phones were only used for communication purpose, but now mobile phones does everything!, as said earlier with growth of technology ,many  aspects of gadgets  have evolved and camera is one of the main aspect among them, as of now let’s concentrate on camera.

Now a days mobiles without a good camera is of no use, indeed mobiles are being promoted as, its having quality camera as a one of its main feature. Hence camera is one of the most important feature of mobile.
When we hear a word camera, usually we come across words like focal length , aperture , depth of field and so many. So let’s see few among them

Focal length –  Focal length which is usually denoted in millimeters(mm) is known as the distance between point of convergence and  image sensor. Point of convergence is nothing but, it’s a point at which all light rays converge. Focal length number tells the angle of view, i.e it tells us that how much of the seen is captured. If the focal length is lower than the area covered is larger resulting in lesser magnification, if the focal length is larger than the area covered is larger resulting in more magnification.

Aperture – Aperture can be defined  as the amount of light that enters the lens ,hence larger the aperture more light enters the lens and smaller the aperture less light enters the lens basically aperture controls the depth of field ,lets see the depth of field later.
Aperture is basically expressed in terms of F-stops ,if F-stop is large then aperture is small and if F-stop is small then aperture is large, in simple words both are indirectly proportional,

If the aperture is large (smaller F stop ) then the subject in image will be focused efficiently so that it blurs the background , this is also known as depth of field or portrait photography i.e depth of field mainly concentrates on focusing the particular subject and blurs the background. If the aperture is small (larger F-stop) then the area covered by the image is large i.e it does not focuses on particular subject and this concept is used in landscape photography.