Have you ever wondered how a camera captures a particular scene and then converts it into a digital format? Many people would have done so but they may not know the answer to it.
In this guide, we will explore how does a digital camera work? We will also touch on the following topics:
- Components of a digital camera
- Uses of various parts of a camera
- How do cameras take pictures?
- Tips on using digital cameras
- Frequently Asked Questions
The working of digital cameras has been a hot topic for discussion among photographers. Even those who take random pictures everyday want to know how these devices work. The working knowledge of such electronic devices allows a user to understand them better and take maximum output from a device. Therefore, we have brought this guide which will explain all about how a digital camera works?
What is a digital camera?
Digital cameras are devices that take photos in a digital format. Almost all new cameras manufactured today are digital due to the advancement in technology. Traditional analog cameras have been replaced because people want fast access to media these days. The development of modern cameras traces back to the invention of transistors (MOSFETS) that formed the image sensors using semiconductor and CMOS technology. Several devices were made during the 1960s and 1970s as the systems were evolving. The first electronic camera was invented by Kodak in 1975. Soon, other brand like Fujifilm and Olympus developed their electronic cameras.
The initial devices were limited to professional organisations only. It was the advancement in signal processing and data compression that made it possible to produce commercial digital cameras which could take hundreds of pictures at one time. Currently, digital cameras can be found in smart phones, computers, televisions and many other devices. Modern devices have multiple connectivity options and features to produce high quality images and videos.
Components of a digital camera
Before we move on to discover how do cameras work, let’s investigate the type of components existing in the cameras which form the overall device.
This is the first thing that you will notice on a camera. It captures the light that falls into the device. All lenses are made of circular glass to allow light to pass through. The aperture size determines the opening of the lens and the amount of light that passes through. It is a critical element in professional photography because it determines the depth and focus of the image. Most Digital Single Lens Reflex (DSLR) cameras have interchangeable lens which increase the versatility of the device. Smaller digital cameras usually have fixed lens design but their aperture and autofocus settings can be changed easily.
The shutter is situated in front of the lens and it controls the lens exposure to light as you capture the photographs. It operates with the button that you press when taking a picture. Shutter also serves in taking burst mode photos, videos and various other types of images. Its speed can be controlled through settings which allow highly crisp images.
The image sensor is a key item in producing the pictures in the digital format. It collects the light captured by the lens and converts it into electrical signals which are sent to the analog to digital converter (ADC). The pixels present on the sensor are responsible for detecting the light transmitted. They are made from complementary metal oxide semiconductor (CMOS) or charged coupled device (CCD) in new devices. If you ask how do cameras take pictures, the sensor would be the first thing which you should explain as an answer.
A viewfinder is the actual space where you see the image from. There are 2 types of viewfinders used in digital camera: electronic and optical.
Electronic Viewfinder (EVF)
These viewfinders are found in mirrorless cameras which are becoming quite popular these days. The image is formed electronically at a small display. It does not use mirrors for projection. The benefit is that the system is very lightweight and compact so the devices using EVF are quite small in size.
Optical Viewfinder (OVF)
Optical viewfinders are the most widely used systems in digital cameras. All DSLRs use these viewfinders. There are optical mirrors that are positioned at specific angles which provide the light from the lens to the image sensor. Users are able to see the image directly so you get a clear representation of the scene. This system is a bit heavy but it consumes less battery life. It is preferred in professional photography.
- Image Processor
Every electronic device needs efficient software to run it properly. The computation of images also requires processors that can deal with various commands and images quickly. The purpose of this component is to process all the digital signals received from the image sensor and produce the actual photograph with the required results. Modern processors can do a range of functions such as scene recognition, colour adjustment, etc.
- LCD Screen
Almost all modern digital cameras have LCD displays which show you the images and videos on the spot. The screen is the main part of user interface as it allows you to adjust the various settings in the camera and view the images and videos simultaneously. The average size of screens is 3 inches and most of them are movable to adjust the viewing angles of the photographer.
- Flash Light
The flash is used to increase the light level for the surroundings. They are usually placed at the top of the lens or directly besides it. It helps a lot in low light conditions. All cameras have built in flash lights but there are external flashes available as well. In many cases, the flash of the camera is not enough so professionals use separate lights to make the scene look brighter.
- User Controls
To send commands to the digital camera, the user interacts through the controls in the form of buttons or levers. The main button is for power which turns on or off the camera and it is usually located on the top. Besides that, you will find the shutter or capture button from which you take the pictures or start recording video. Other controls to adjust various settings are located with the LCD screen on the main body of the camera. In most cameras, they are located in a circular style which can be changed by rotating it. Screens with touch interface also have options that can be adjusted through them.
Apart from the basic parts of a digital camera, there are a number of accessories without which, it would remain incomplete. These include memory cards, tripod stands, holding straps, carry bags and many more. In several products, you get all of these accessories along with the package which makes it convenient for a user to start shooting beautiful pictures and videos.
How Does A Digital Camera Work
After reviewing the components of the devices, you must have gotten an idea on how a digital camera works? Let’s explore the process step by step.
1. The first thing that you do is to hold the camera behind the scene you want to capture. You can view the surroundings from the LCD screen or the eyepiece and position your camera accordingly. If you wish to capture an extra steady shot, use a tripod stand.
2. Make sure to adjust all the settings such as zoom, aperture, ISO and HDR according to your requirements. Press the shutter button to capture the photo. All analog cameras and digital devices work on the principle of light. Therefore, light enters through the lens. The shutter and aperture settings control how much light is to enter.
3.The light travels to image sensor which is made up of a photosensitive material. The photosites present in the sensor are called pixels. The CCD or CMOS senor then outputs an electrical signal which is equal to the photons received.
4. This voltage is then transferred to the ADC which is found in the image processor.
5. The image processor tunes the image further to produce the best possible output using the signal processing algorithms.
6. The varying signals are converted into discrete values (digital numbers), which is the main reason we call these digital cameras.
7. The digital data is stored in the memory of the camera which is usually an external memory card on most devices.
How does a film camera work?
The working of a film camera is not much different to its digital counterpart. Both rely on the reflective properties of light. The key difference is that the sensor in film cameras is a piece of photo sensitive material known as the film. The light travelling from the lens hits the film which reacts through the light sensitive materials on it. The film is then processed using a mixture of chemicals to produce the actual image in hard form.
Tips on using a digital camera
There are some points that users must practice while taking pictures from digital cameras.
1- Take time to learn about the camera’s settings and functions in detail. Nowadays, you can watch video tutorials on the Internet regarding every product.
2- Practice taking pictures everyday of random things. Better to start in daylight so that light is not an issue.
3- Try to use every setting available on the device. Change the aperture, ISO, brightness, contrast and mode settings to see the difference that they make on the images.
4- View the images in full screen on computer to get the actual result visible.
5- Keep the lens and viewfinder clean so that dust does not intervene in the pictures.
Frequently Asked Questions
1. How does a camera form an image?
The cameras use light to form an image. The light travels through the lens after reflecting from the scene and strike at the image sensor. The sensor converts the light pixels into voltage signals. They are then converted into digital format by ADC which produces the photo and stores it in the memory. You can view the images on the LCD screens on the spot.
2. Can I use my Canon camera as a webcam?
Canon cameras can be used as webcam by connecting them the computer. If the camera has built in system for webcam interface, then it is best to use it otherwise you can use external applications which enable its functionality as a webcam. Another method is to connect it via HDMI cable to the computer so that the screen is shared directly.
3. How does a digital video camera work?
Digital video cameras use binary numbers to store the video by creating a stream of data corresponding to the frames in the moving scenes. The information is stored on the memory of the camera which is very easy to view and share. Light enters the lens and hits the image sensor which converts it into voltage signals. These are then changed into digital stream which is the videos that forms later on.
4. Can you use a camcorder for live streaming?
Yes, camcorders can be used for live streaming provided that they have Wi-Fi and web sharing options. You will need to upload or broadcast the videos on the spot which needs Wi-Fi. Another option is to install relevant software on the computer and connect the camcorder through USB cable to start streaming. These days, most people use smartphones for live streaming which has reduced the needs of buying special camcorders for the purpose.
In this guide, you have seen how does a digital camera work by first observing the various parts of the devices and then their functions in a step by step manner. All elements like lens, sensor, shutter, LCD screen and user controls are essential for the working of a camera. If you know about the role of each component, it will help you in understanding the photography in a better way. Beginners often suffer in insufficient knowledge about the cameras they use which results in bad photos. Therefore, it is important to study about the devices before you actually start using them.
We sincerely hope that you liked this guide on how cameras work. We have tried to cover all necessary information is a simple manner. Please share your feedback below in the comments section.