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DSLR camera working principle explained

Getting better at photography involves knowing your camera gear in and out. Ever wondered what happens inside your DSLR camera as soon as the shutter button is pressed? What all steps are involved and how the final image is captured?  As a photography beginner,  it is completely normal to feel curious about what's inside your digital camera. Even as a professional, it is always great to see all the fascinating stuff that happens inside a digital camera. A few very similar questions related to the working of a DSLR camera include: 
How does a DSLR camera work?
DSLR camera working principle.
DSLR camera working procedure.
How does DSLR shutter work?
In this post, I will talk about various architectural parts of a DSLR camera and how they work together in sync with each other to produce beautiful photos.
Working of a DSLR camera
Without much delay, let's focus on the path travelled by the light inside a digital camera in default non-operational state. At the very first step, it passes through the lens opening(aperture) and enters the DSLR camera. The size of this lens opening goes bigger or smaller depending on the F value used. On entering inside the DSLR camera, light hits a mirror. This mirror is at a 45-degree angle and reflects the incoming light from the lens into the reflecting mechanism assembly. 
There is a focusing screen located before reflecting mechanism assembly which helps to see focal points and lock focus on a particular point. Those small red or green coloured dots that you see from the viewfinder are coming from focusing screen. Once light enters the reflecting mechanism assembly, it changes direction 2 times. The role of reflecting mechanism is to show real life photo in a proper orientation and also direct the light from mirror to viewfinder. This reflecting mechanism assembly can either be made of pentamirror or pentaprism as discussed in the previous article. Viewfinder, as the name suggests, helps the photographer to see how the scene looks like and compose the shot.

How it works? 
As soon as the shutter button is pressed, the mirror flips up and goes out of the way of light.  Due to this, light begins to travel a straight path as there is no mirror involved. The shutter and digital camera sensor are now in the way of light. Based on the value of shutter speed, the shutter will open, thus exposing the sensor for the duration of shutter speed. The sensor unit senses the light and all the sensor circuitry comes in action. The image below explains the mirror flip-up state and how the light rays hit the sensor. Mirror flip up leads to darkness in the viewfinder. As a user, you won't be able to see anything through the viewfinder. This is easy to notice during long exposure shots.  
Once light hits the imaging sensor, it gets converted into mini bursts of charge. This is achieved with the help of small photosites ( containing photodiodes ) located on the sensor. There are about million photosites available on a given camera sensor surface. The charge is then converted into an analog signal, followed by digitization of this signal to numbers that computer can understand. This process is done with the usage of an analog to digital converter. 
DSLR camera working procedure
Once a digital copy of the scene is generated in the form of either a raw file or jpeg, it gets written to the storage memory card. This is how we get images from a DSLR camera with the press of a shutter. So many parts working together all resulting in an image thought out by the photographer, digital imaging technology is just brilliant. Hope you learned something new in this post, share the photography love by sharing this post. 


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