How Does A DSLR Camera Work? | A Layman’s Guide
How Does A DSLR Camera Work? | A Layman’s Guide: More often than not in life we simply accept that things work without thinking about the reality of how. That’s not a bad thing, as everything in life is becoming streamlined in a manner in which you don’t need to be asking these questions. But if you’ve ever been the type of person to regularly ask google questions such as – “Is sand called sand because it’s where the sea and land meet?”, than we’ve got you covered with a guide on ‘How Does a DSLR Camera Work?’ Read on as we’ll explain how a DSLR camera works.
| How Does A DSLR Camera Work? |
The Basics To How A DSLR Camera Works
To understand how a DSLR camera works, you need to remind yourself of the mantra that photography is all about capturing light. An image taken by a camera is simply showing you the light which has entered through the lens, and has been processed into an image.
The trick to a DSLR or any camera is being able to turn light into a working, and recognizable image much like a working human eye does. The two most important parts to a camera are the sensor and the processor – this is the brain of the camera and where all the magic happens.
The Two Different Camera States
Essentially a DSLR camera is very similar to a working eye as both consist of mechanisms which allow light to enter and travel to a point in which light rays can be arranged in a manner to form vision.
There are two very different states in which the camera can be in. The first is a stationary/in-active state, this is when you merely look through the lens and don’t press the shutter release button to take a photo. The second is an active state, this is when you’re taking a photo and the shutter release button has been pressed. During each state the camera works a little differently.
In-Active Camera State
Light enters the camera through the lens and travels to the reflex mirror, a small mirror inside the camera which is slanted at an angle of 45 degrees. The reflex mirror is built in a similar manner as a periscope, as it’s designed to bounce the light which has entered through the lens and redirect it towards the eyepiece. The light which is bounced from the reflex mirror is redirected to the pentaprisim at the top of camera, with the light being redirected two more times within the pentaprisim by mirrors to the eyepiece.
In short in order for you to see an image in the eyepiece, light has bounced around several times within the camera to reach the eyepiece. The use of mirrors is a simple, but effective trick in bouncing light. It’s essentially what children use when playing cops and robbers to see around corners.
Interestingly it is from the reflex mirror inside a DSLR (Digital Single Lens Reflex) from which the camera type gains its name. This is due to the reflex mirror being a single mirror.
Active Camera State
This state is when things become a little more interesting. When a camera is active and taking a photo, light enters through the lens once again, however where it travels to is a little different. Instead of the light hitting the reflex mirror and being redirected towards the eyepiece, the light now travels to the camera sensor for processing.
The main point of difference between an active and an in-active state is the reflex mirror, the camera shutter and what they’re doing. When the camera is active and taking a photo the reflex mirror folds up and blocks any light from entering the pentaprisim, and by extension the eyepiece. That’s why when you take a photo you can’t see anything, as the light has been blocked.
By the reflex mirror folding up it allows light to reach the camera shutter. The camera shutter remains open for as long as the duration of the photo. This can range from as long as 30 seconds, or to as quick as 1/800th of a second. During the time the camera shutter is open, it’s creating an opportunity for light to reach the camera sensor unobstructed. It is at this point the camera sensor processes light into an image. The camera sensor records all the light information which was sent through the camera to make a photo.
The camera sensor also adjusts for the shutter speed, the aperture, and the ISO on the camera all at the same time. It’s truly remarkable how the camera is able to calculate all this information in a matter of seconds. Once the camera has finished taking a photo, the camera shutter than closes which is followed by the reflex mirror retracting back to its stationary position. This allows light to once again reach the eyepiece.
TLDR; How Does A DSLR Camera Work
When you press the shutter button two main parts move – the reflex mirror and shutter. When they’re active they allow light to reach the sensor. Once light has hit the sensor light is transformed and processed into an image. Once an image has been taken both the reflex mirror and shutter retract back to their original positions.
How Does A DSLR Camera Work? | A Layman’s Guide