Technology behind digital camera
The digital camera is one of the great examples of the technology. Digital cameras give a whole new meaning to the idea of painting by numbers. They capture and record images of the world around us using digital technology. Not only that, they store photographs as long strings of numbers. Do you know how the technology works behind this digital camera? Let’s find out through this article.
What is Digital camera?
A digital camera or digicam is a camera that captures photographs in digital memory. Most cameras produced today are digital. High-end, high-definition dedicated cameras are still commonly used by professionals.
How does technology work behind the digital camera?
Digital cameras look very much like ordinary film cameras but they work in a completely different way. When you press the button to take a photograph with a digital camera, an aperture opens at the front of the camera and light streams in through the lens. So far, it's just the same as a film camera. But there has no film in a digital camera. Instead of that, there has a piece of electronic equipment that captures the incoming light rays and turns them into electrical signals. This light detector is one of two types, either a charge-coupled device (CCD) or a CMOS image sensor.
If you've ever looked at a television screen closely, you will be noticed that the picture is made up of millions of tiny colored dots or squares called pixels. Laptop, LCD computer screens also make up their images using pixels, although they are often much smaller too see. In a television or computer screen, electronic equipment switches all these colored pixels on and off quickly. Light from the screen travels out to your eyes and you see a large, moving picture.
In a digital camera, exactly the opposite happens. Light from the thing you are photographing zooms into the camera lens. This incoming "picture" hits the image sensor chip, which breaks it up into millions of pixels. The sensor measures the color and brightness of each pixel and stores it as a number. Your digital photograph is effectively an enormously long string of numbers describing the exact details of each pixel it contains.
Once a picture is stored in the numeric form, you can do all kinds of things with it. Plug your digital camera into your computer, and you can download the images you've taken and loaded them into programs like PhotoShop to edit them. Some of these image-editing techniques are built into more sophisticated digital cameras. You might have a camera that has an optical zoom and a digital zoom. An optical zoom means that the lens moves in and out to make the incoming image bigger or smaller when it hits the CCD. A digital zoom means that the microchip inside the camera blows up the incoming image without actually moving the lens. So, just like moving closer to a TV set, the image degrades in quality. In short, optical zooms make images bigger and just as clear, but digital zooms make images bigger and more blurred.
Types of digital camera
Compacts digital cameras
Compact cameras are intended to be portable (pocketable) and are particularly suitable for casual "snapshots". Compact cameras are usually designed to be easy to use. Almost all include an automatic mode, or "auto mode", which automatically makes all camera settings for the user. Some also have manual controls. Compact digital cameras typically contain a small sensor which trades-off picture quality for compactness and simplicity; images can usually only be stored using lossy compression (JPEG). Most have a built-in flash usually of low power, sufficient for nearby subjects. A few high-end compact digital cameras have a hot-shoe for connecting to an external flash. Live preview is almost always used to frame the photo on an integrated LCD.
Rugged compact cameras typically include protection against submersion, hot and cold conditions, shock and pressure. Terms used to describe such properties include waterproof, freezeproof, heatproof, shockproof and crushproof, respectively. Nearly all major camera manufacturers have at least one product in this category. Rugged often lack some of the features of the ordinary compact camera, but they have video capability and the majority can record sound. Most have image stabilization and built-in flash. Touchscreen LCD and GPS do not work underwater.
GoPro and other brands offer action cameras which are rugged, small and can be easily attached to the helmet, arm, bicycle, etc. Most have a wide angle and fixed focus and can take still pictures and video, typically with sound. The rising popularity of action cameras is in line with many people desiring to share photos or videos in social media. Many competitive manufacturers of action cameras result in many options and lower, competitive prices, and nowadays, cameras are sold bundled with waterproof housings, accessories, and mountings compatible with the popular GoPro.
The 360-degree camera can take a picture or video 360 degrees using two lenses back-to-back and shoot at the same time. Some of the cameras are Ricoh Theta S, Nikon Key mission 360 and Samsung Gear 360. Nico360 was launched in 2016 and claimed as the world's smallest 360-degree camera with size 46 x 46 x 28 mm (1.8 x 1.8 x 1.1 in). With virtual reality mode built-in stitching, Wifi, and Bluetooth, live streaming can be done. Due to it also being water resistant, the Nico360 can be used as an action camera. There are tend that action cameras have capabilities to shoot 360 degrees with at least 4K resolution.
Bridge cameras physically resemble DSLRs and are sometimes called DSLR-shape or DSLR-like. They provide some similar features but, like compacts, they use a fixed lens and a small sensor. Some compact cameras have also PSAM mode. Most use live preview to frame the image. Their usual autofocus is by the same contrast-detect mechanism as compacts, but many bridge cameras have a manual focus mode and some have a separate focus ring for greater control.
Mirrorless interchangeable-lens cameras
In late 2008, a new type of camera emerged called mirrorless interchangeable-lens camera (MILC), which uses various sensors and offers lens interchangeability. These are simpler and more compact than DSLRs due to not having a lens reflex system. MILC camera models are available with various sensor sizes.
While most digital cameras with interchangeable lenses feature a lens-mount of some kind, there are also a number of modular cameras, where the shutter and sensor are incorporated into the lens module. The first such modular camera was the Minolta Dimâge V in 1996, followed by the Minolta Dimâge EX 1500 in 1998 and the Minolta AutoFlash 3D 1500 in 1999. In 2009, Ricoh released the Ricoh GXR modular camera.
Digital single-lens reflex cameras
Digital single-lens reflex cameras (DSLR) use a reflex mirror that can reflect the light and also can swivel from one position to another position and back to initial position. By default, the reflex mirror is set 45 degrees from horizontal, blocks the light to the sensor and reflects light from the lens to pentamirror/prism at the DSLR camera and after some reflections arrive at the viewfinder. The reflex mirror is pulled out horizontally below the pentamirror/prism when the shutter release is fully pressed, so the viewfinder will be dark and the light/image can directly strike the sensor at the time of exposure.
Digital Single Lens Translucent (DSLT) cameras
A DSLT uses a fixed translucent mirror instead of a moving reflex mirror as in DSLR. A translucent mirror or transmissive mirror or semi-transparent mirror is a mirror which reflects the light to two things at the same time. It reflects it along the path to a pentaprism/pentamirror which then goes to an optical viewfinder (OVF) as is done with a reflex mirror in DSLR cameras. The translucent mirror also sends light along a second path to the sensor. The total amount of light is not changed, just some of the light travels one path and some of it travels the other. The consequences are that DSLT cameras should shoot a half stop differently from DSL.
A rangefinder is a device to measure subject distance, with the intent to adjust the focus of a camera's objective lens accordingly (open-loop controller). The rangefinder and lens focusing mechanism may or may not be coupled. In common parlance, the term "rangefinder camera" is interpreted very narrowly to denote manual-focus cameras with a visually-read out optical rangefinder based on parallax.
Line-scan camera systems
A line-scan camera traditionally has a single row of pixel sensors, instead of a matrix of them. The lines are continuously fed to a computer that joins them to each other and makes an image. This is most commonly done by connecting the camera output to a frame grabber which resides in a PCI slot of an industrial computer. The frame grabber acts to buffer the image and sometimes provide some processing before delivering to the computer software for processing.
Stand-alone cameras can be used as a remote camera. One kind weighs 2.31 ounces (65.5 g), with a periscope shape, IPx7 water-resistance, and dust-resistance rating and can be enhanced to IPx8 by using a cap. They have no viewfinder or LCD. The lens is a 146-degree wide angle or standard lens, with fixed focus. It can have a microphone and speaker, And it can take photos and video. As a remote camera, a phone app using Android or iOS is needed to send live video, change settings, take photos, or use time lapse.