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How film-based cameras work explained

In order to understand how a film camera works, you have to analyze how the technology has developed over the last century. The film camera has been an essential tool in the development of our modern world. Although most of us consider the camera as a major invention of the last century, it is ironic to see that the concepts used in the development of this device can be compared to the concept used back in the ancient times.

The concept of photography is based on a concept called camera obscura. This states that if you poke a hole in a dark room, the light passing through the hole will be flipped upside down, but will retain its color and perspective. This theory with such peculiar behavior was studied and noted by ancient inventors such as Mozi, Aristotle, and Alhazen, all making note of this peculiar behavior.

Check out the youtube video below to understand how a film camera works:

It wasn’t until 1490 that an Italian inventor by the name of Leonardo DaVinci used this concept to create a tracing machine. This took the concept of camera obscura and projected the image onto a piece of parchment that the inventor could then trace. Camera obscura devices continued to gain popularity into the 1700’s. Some historians claim that Rembrandt used this technique on some of his most famous works of art.

In 1774 Johann Heinrich Schulze discovered that substances mixed with silver nitrate are photoreactive. This means that they react to light. The modern camera was on the tip of inventor’s fingertips, but sadly, this knowledge was not capitalized on until 1826 when an inventor by the name of Joseph Nicephore Niepce developed a technique called heliography. This combined all of the previous camera obscura techniques, and the made possible for the first photograph to be captured.

The first photographs took several days to develop and the clarity left much to be desired, but for the time it was remarkable. Niepce’s partner, Louis Daguerre, continued his experiments after Niepce’s death. By 1833, Daguerre had documented what would be known as the first working photographic process. This early camera was called the Daguerreotype, and by 1839, the French government had purchased the rights to this device.

The photography craze can be traced to this point, with many photography firsts happening in quick successions, such as the first photograph of a human being. This person just happened to be getting his shoe-polished on the street corner that was photographed. By pure luck, he was sitting still long enough to capture him in surprising clarity for the time. Shortly thereafter the first selfie was taken by Robert Cornelius in 1839.

Once people realized you could capture the beauty of humans on film, it didn’t take long for the first nude photographs to begin to emerge. In 1840 Henry Fox Talbot revealed his new version of the camera, the Calotype. What made this invention so critical to the evolution of photography was the use of negatives. This allowed paper copies to be made. This invention could have spawned another photographic revolution except for the fact Calotype tried to charge expensive licensing fees that eventually caused his invention to fall to the background. He spent the rest of his life fighting licensing lawsuits and eventually he gave up his quest to make money off of his invention.

A man named Sir John Hershel first used the term photography. He came up with the word photography by combining the Greek words light and drawing. By 1850, mobile photo studios began to become very popular. This is partly because exposure times had been dropped to around three minutes, which meant you had to stand perfectly still for three minutes to get a clear photograph. People would go to extreme measures to stay still even using braces and other forms of body support to keep them frozen in place.

As photography progressed so did the world of photo editing. One of the most famous examples of early photo editing is a picture of Abraham Lincoln where his head is placed upon another body to provide him with a more noble stature.

In 1861 the first color photograph was revealed to the world, which led to the invention of the Gelatin Dry Plate camera. What made this so revolutionary was the fact that it was small and portable. Up until this time, cameras were heavy and required a tripod. The film camera was well on its way to becoming the better-known versions we recognize today.

In 1885, a man named George Eastman decided to start a new company by the name of Kodak, and he would later go on to change photography forever with the invention of roll film. The Kodak camera came preloaded with 100 exposures. These early cameras would need to be sent back to the factory to have their film developed. In 1900, Kodak unveiled its new box camera design which was smaller, lighter, and more affordable than its predecessors, opening the door for new photographers around the globe.

Although very close to our current 35mm cameras, they were still much larger and continued to require the entire unit to be sent back to Kodak for development. Another inventor named Oskar Barnack took notice of this and developed the first 35mm camera. This camera gave photographers unprecedented mobility. It also allowed for more photographers and quicker photo taking experiences, which led to an explosion of iconic photographs around the world. A half-century after Kodak released its box camera design another inventor develops the first SLR (single lens reflex) the camera.

Understanding how a film camera works is much easier in hindsight. These early inventors spent years of their life improving upon the inventions prior to creating our modern film cameras. It is hard to imagine the world without photography. Film cameras have literally changed the world and even though the first digital camera process was invented in 1975, it wasn’t until the 1990’s that people began to convert away from film cameras. The film has a very warm and traditional feel to it, and that is why many people still prefer to use this technique of photography over digital options.

How film-based cameras work explained

People have been using camera and film for more than ­100 years, both for still phot­ography and movies. There is something magical about the process — humans are visual creatures, and a picture really does paint a thousand words for us!

Despite its long history, film remains the best way to capture still and moving pictures because of its incredible ability to record detail in a very stable form. In this article, you’ll learn all about how film works, both inside your camera and when it is developed, so you can understand exactly what is going on!

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Basic Cameras

Most kids these days haven’t used a camera that uses film. Today, digital cameras are the most commonly used. Many people have a digital camera on their phones. Whether a camera is digital or uses film, there are some basic commonalities among them. They can capture a moment in time called a picture. So, what happens when you push the button on a camera to take a picture?

Film Camera

How film-based cameras work explained

It’s All About Light

The very first thing that has to happen when working a camera is that light has to pass through the lens. The lens is a glass plate that covers the opening to the camera’s body. The lens directs from an object to the film when the shutter opens.

When you push the button on a camera, it opens a shutter, which is a lid that protects the film. The shutter is like your eyelids, and when you open them, then the light comes in. On a camera, the shutter opens and closes really fast. It only wants to let enough light in to capture the image and then close before it gets too much light. The film is stored in the camera’s body and has special chemicals on it that cause the film to change colors when light touches it.

What’s interesting is the image on the film is the opposite of what you see. For example, if you were to take a picture of a dalmatian dog, then the spots would be white and the background fur would be black. This is called a negative film. The negative film is the strip of plastic that captures the image through a chemical process in opposite colors. Once the film is processed in other chemicals, then the colors reverse and the image appears as it did when the button on the camera was pushed.

The trees are light and the sky is dark in the film negative.

How film-based cameras work explained

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Are Digital Cameras the Same?

Taking pictures today can be easier because you can see the image immediately after you take the picture. Digital cameras have a lens and body just like film cameras, but the main difference is the image is captured by a sensor instead of film. The sensor in a digital camera has a whole bunch of squares like a checkerboard called pixels. Each square will take in a charge of the color and brightness captured from the light. The colors of the image are stored in the computer part of a digital camera and can be used to print pictures.

The rectangular piece in the middle is a digital camera sensor.

How film-based cameras work explained

Lesson Summary

Cameras capture images of a specific time that can be printed on picture paper. There are two main types of cameras, film and digital, with similar parts and processes. They both have a lens, shutter, and camera body. In both types of cameras, light passes through the lens while the shutter (lid) opens and is captured by film or a sensor. A negative is created with film whereas a file with colored pixels is stored in a digital camera.

Film Options

­When you purchase a roll of film for your camera, you have a lot of choices. T­hose products that have the word “color” in their name are generally used to produce color prints that you can hold in your hand and view by reflected light. The negatives that are returned with your prints are the exposures that were made in your camera. Those products that have the word “chrome” in their name produce a color transparency (slides) that requires some form of projector for viewing. In this case, the returned slides are the actual film that was exposed in your camera.

Once you decide on prints or slides, the next major decision is the film speed. Generally, the relative speed rating of the film is part of its name (MYColor Film 200, for example). ISO and ASA speed ratings are also generally printed somewhere on the box. The higher the number, the “faster” the film. “Faster” means increased light sensitivity. You want a faster film when you’re photographing quickly moving objects and you want them to be in focus, or when you want to take a picture in dimly lit surroundings without the benefit of additional illumination (such as a flash).

When you make film faster, the trade-off is that the increased light sensitivity comes from the use of larger silver-halide grains. These larger grains can result in a blotchy or “grainy” appearance to the picture, especially if you plan to make enlargements from a 35-mm negative. Professional photographers may use a larger-format negative to reduce the degree of enlargement and the appearance of grain in their prints. The trade-off between photographic speed and graininess is an inherent part of conventional photography. Photographic-film manufacturers are constantly making improvements that result in faster films with less grain.

A slow-speed film is desirable for portrait photography, where you can control the lighting of the subject, the subject is stationary, and you are likely to want a large print from the negative. The finer silver-halide grains in such film produce the best results.

The advanced amateur photographer might encounter additional film designations such as tungsten balanced or daylight balanced. A tungsten-balanced film is meant to be used indoors where the primary source of light is from tungsten filament light bulbs. Since the visible illumination coming from a light bulb is different than from the sun (daylight), the spectral sensitivity of the film must be modified to produce a pleasing picture. This is most important when using a transparency film.

Film comes with an ASA (American Standards Association) or ISO (International Standards Organization) rating that tells you its speed. The ISO and ASA scales are identical. Here are some of the most common film speeds:

A common misconception surrounds today’s digital cameras: Because these cameras don’t use film and because they produce pictures as data files, many folks think that digital cameras must use a radically different method of capturing images. Actually, your family film camera and that power-hungry, battery-munching digital camera you got for Christmas are remarkably similar in most respects.

A film camera has a shutter that opens for a set amount of time (usually a fraction of a second), admitting light into the body of the camera through at least one lens. (Of course, that lens can be adjusted to bring other objects at other distances into focus, or different lenses can be tacked on.)

How film-based cameras work explained

As the figure illustrates (up to this point, anyway), your film camera and its digital brethren work exactly the same.

How film-based cameras work explained

The big difference is the method that each of these two types of cameras uses to record that incoming light. To wit:

A film camera uses a strip of light-sensitive celluloid coated with silver halide, which retains the image. The film must later be developed, and the negatives and positives that are produced can be used (reproduced, usually on photographic paper) to make copies of the photograph.

A digital camera, on the other hand, uses a grid (or an array) of photosensors to record the incoming pattern of light. Each sensor returns an electrical current when it’s struck by the incoming light.

Because the amount of current that’s returned varies with the amount of light, your digital camera’s electronic innards can combine the different current levels into a composite pattern of data that represents the incoming light — in other words, an image in the form of a binary file.

If you’ve read some of my other books on CD/DVD recording, photography, and scanning, you already know about binary, which is the common language shared by all computers. Although your eye can’t see any image in the midst of all those ones and zeroes, your computer can display them as a photograph — and print the image, if you like, or send it to your Aunt Harriet in Boise as an e-mail attachment.

How does the image file get to your computer? That’s a very good question; naturally, no one wants to carry a PC around just to shoot a photograph. Most digital cameras store the image file until you can transfer (download) it to your computer — other digital cameras (and many smartphones) can now directly transfer the photos you take to your PC, or even Facebook or Flickr wirelessly!

Different types of cameras use different methods of storing the image files:

RAM cards: Random access memory (RAM) cards (the most common storage method) are removable memory cards that function much like the memory modules used in a USB flash drive. Some memory cards are proprietary, but some cards are interchangeable with netbooks, smartphones, and tablet PCs.

The most popular types of media include CompactFlash, SmartMedia, and Memory Stick cards, generally ranging from 512MB to 128GB of storage. When the card is full of images, you either download the images from the card (presumably to your PC) to free up space or eject it and “reload” with a spare, empty card.

Hard drives: Yep, you read right — some cameras have their own onboard hard drives, and others use tiny removable hard drives that are roughly the same size as RAM cards. Naturally, these little beauties can easily store hundreds of gigabytes of your images.

If you’re wondering approximately how many images you can fit onto a specific RAM card, remember that most 10- to 16-megapixel (MP) cameras now produce images of about 2 to 6 megabytes (MB) at their highest-quality mode.

How film-based cameras work explained

In 1947, an inventor named Edwin Land introduced a remarkable innovation to the world — a film that developed itself in a matter of minutes. This new instant camera technology was a huge success for Land’s company, the Polaroid Corporation. In 1949, Polaroid made more than $5 million in camera sales alone! Over the proceeding 50 years, the company carved out its own special niche, selling millions of instant cameras and more than a billion rolls of instant film.

In this article, we’ll find out what’s actually happening inside instant film while you’re waiting for the image to appear. While it may seem like magic, the process is really very simple.

Instant camera film is pretty much the same thing as regular camera film, with a few extra elements. Before we get to those crucial additions, let’s briefly examine film photography in general.

The basic idea of film is to capture patterns of light using special chemicals. The camera briefly exposes the film to the light coming from a scene (typically for a small fraction of a second), and where the light hits the film, it starts off a chemical reaction.

Normal film consists of a plastic base that is coated with particles of a silver compound. When this compound is exposed to a large number of light photons, it forms silver atoms. Black-and-white film has one layer of silver compound, while color film has three layers. In color film, the top layer is sensitive to blue light, the next layer is sensitive to green and the bottom layer is sensitive to red. When you expose the film, the sensitive grains at each layer react to light of that color, creating a chemical record of the light and color pattern.

To turn this into a picture, you have to develop the film using more chemicals. One chemical developer turns the exposed particles into metallic silver. The film is then treated with three different dye developers containing dye couplers. The three dye colors are:

  • Cyan (a combination of green and blue light)
  • Magenta (a combination of red and blue light)
  • Yellow (a combination of green and red light)

Each of these dye-coupler types react with one of the color layers in the film. In ordinary print film, the dye couplers attach to particles that have been exposed. In color slide film, the dye couplers attach to the non-exposed areas.

Developed color film has a negative image — the colors appear opposite of the colors in the original scene. In slide film, the two dyes that attach to the unexposed area combine to form the color captured at the exposed layer. For example, if the green layer is exposed, yellow and cyan dye will attach on either side of the green layer, but the magenta dye will not attach at the green layer. The yellow and cyan combine to form green. (For more in-depth informa­tion on the entire process, see How Cameras Work and How Photographic Film Works.)

The instant-camera developing process combines colors in the same basic way as slide film, but the developing chemicals are already present in the film itself. In the next section, we’ll see how the developers are combined with the color layers to form the picture.

Despite the invention of extraordinary life-like-image capturing cameras actualized by the electronic revolution, anachronistic folks still adore polaroid cameras for the delightful nostalgia they arouse. Polaroid cameras were truly a revolutionary invention. Prior to their existence, colored images were developed through a tedious process of subjecting negatives to coloring dyes in a darkroom. The images wouldn’t be ready to be viewed for days.

However, what Harvard inventor Edwin Land did was compress the darkroom and its myriad chemicals into a single camera. Land then decided to sell his invention. He founded the Polaroid Corporation and made a fortune of $5 million in camera sales in 1949! Due to his corporation’s immense success, just like Xerox, the corporation’s name became synonymous with the technology’s name – instant cameras are still commonly referred to as Polaroid cameras and instant film as Polaroid pictures. So, how do they work?

How film-based cameras work explained

(Photo Credit : Pixabay)

The Basics

At the turn of the century, we began digitizing images, transmuting them into pixels and storing them in memory cards. However, there was no such technology back in the 1950s. Back then, film couldn’t be developed instantaneously. A film is a plastic sheet covered with silver halides. A halide refers to any of the electronegative elements that reside in group 7, the halogen group, or simply, the column beside the noble gas column. Thus, a silver halide refers to any combination of silver and either fluorine, chlorine, iodine, bromine etc. These films are extremely sensitive to light, so they are processed and manufactured with space-dark coatings to avoid any pre-exposure to light.

When you press the ‘click’ button on the camera, in a fraction of a second, the shutter opens, and the light-sensitive film is exposed to the incoming light, to the scene you wish to capture. The incident light energy disturbs the molecules of silver halide covering the film. The energy ionizes the compound and extracts individual metallic silver atoms. The amount of silver atoms produced is proportional to the amount of exposed light. Thus, if you’re capturing a tree standing in broad daylight, the area of film exposed to the sky would be suffused with more silver atoms than the area exposed to the tree.

How film-based cameras work explained

Due to the dense accumulation of silver atoms, the film exposed to excess light is rendered much darker than the areas that are less exposed. The canvas is now painted in the exact opposite colors of the scene that we wanted to capture. The ‘reverse’ image carved on the film is called a negative image. To produce the original or positive image, like the rules of multiplication, we must take a negative image of this negative image.

If one wishes to generate a black-and-white image, one must expose the negative to light once again. Now, the dark parts prevent the light from passing through, whereas the silver halide in the previously unexposed brighter parts of the film ionizes to produce silver atoms and, therefore, darker colors. The darker areas are now white, and the brighter areas are now dark. The colors are reversed once again, so what is created is the original, positive image!

How film-based cameras work explained

Instant Color Films

The same principle is used to develop colored pictures. While the process back then was carried out in labs, Land compressed the lab into the camera itself. Instant film is covered with not one, but three silver halide coatings. The first coating (from up to down) responds to blue light, the second to green light and the third to red light.

However, remember that when blue, green and red lights fall onto these coatings, the films produced are negatives. Silver atoms in the plates are densely accumulated in those areas that are exposed to more light. In terms of color, the third plate encoded with the information of red light is actually cyan. Similarly, the other two plates are also painted in ‘opposite’ colors: the green plate is covered in magenta and the blue plate in yellow.

How film-based cameras work explained

Deposited below each plate is a coating of the opposite color: yellow below the blue plate, magenta below the green plate and cyan below the red plate. These are known as developing dyes. The last coating at the bottom is black, which ensures that every speck of light is absorbed, or none is reflected, as this light could distort the image.

Just like the case of a black-and-white image, the application of cyan to the red implements a negative of the negative. It cancels the red areas and reacts with the unexposed silver halides in the cyan areas to form red. Similarly, magenta and yellow react with the green and blue coatings, respectively, to implement a negative of the negative. We know that combinations of red, green and blue can create any color there is, so the three positive plates are then overlaid to form the original, colored image.

How film-based cameras work explained

The series of layers stack up like dominoes, and just like a set of dominoes, the chain reaction cannot begin without a trigger. The chemical reaction that forces the dyes to move upwards is triggered by a reactive agent or reagent. The reagent is stored in pouches that are adhered to the iconic white space below a polaroid picture. To apply the reagent over the coatings on the film above, a mechanism inside the camera sends the film between two rollers such that the rollers pop the pouch and smear its contents over the film as the film moves forward. In subsequent models, the reagent was applied to another film that was then deposited over the photographic film.

How film-based cameras work explained

So, as soon as the shutter button was clicked, the film with reoriented silver atoms would be coated with the reagent and a chemical reaction would ensue. The dyes would flow upwards and color the three coatings. Finally, almost immediately, as if by magic, the camera would gradually print a piece of white plastic until it would hang out by its end like the camera’s tongue. The dyes need some time to completely dry, so one can smudge the picture with a Q-tip, to impart a sort of painting effect. The colors that the white plastic exhibits are the result of incident light reflected through the dyes smeared on its surface.

For the simplicity of Land’s revolutionary innovation, he’s considered nothing less than a genius. Also, contrary to popular belief, shaking the plastic is actually bad for the picture.

When it comes to purchasing a lens for your digital camera, the sheer number of options, specifications, acronyms, and features is enough to make anyone throw up their hands in frustration and resort to simply using their smartphone. But dedicated cameras are still worth it , and produce high-quality photos that smartphone cameras just can’t match with their minuscule sensors. Once you know what you’re looking for, and know how different companies brand identical features, it isn’t too difficult to figure out what type of lens you need. With a little education, you can determine which features in your new lens are superfluous, essential, or just nice to have.

Aperture

The aperture on a camera lens functions much like your pupils, opening in accordance with how much light you want to hit the camera’s sensor. Your camera lens’ maximum aperture number, measured in “f-numbers” or “f-stops,” is usually indicated in the same manner on every lens. The aperture range can vary anywhere from f/1.0 to f/22 depending on the lens. You’ll find variations in the presentation—sometimes f/2.8 is shown as “ 1:2.8,” for example— but the numbers indicate the same thing: the maximum aperture of your lens.

The lower the number (f/1.8, for example), the wider the opening, and the more light your lens lets in. Lenses with low apertures (which allow for more light to hit the sensor) also produce that blurred “bokeh” effect, perfect for portraits. If you’re using a zoom lens, you’ll instead see a maximum aperture range, like f/3.5-4.5. The two aperture numbers represent the largest aperture available at your camera’s zoom range. The more you zoom in, the smaller your maximum aperture (leading to that higher 4.5 aperture number).

Focal Length

A camera lens’ focal length (the distance from the lens’ most focused image to the camera’s sensor itself) is written in millimeters. Lenses that lack zoom functionality (like a portrait lens with a fixed focal length of 35mm) have a single focal length, while zoom lenses use two numbers (like 18-55mm) to indicate the range of a lens’ focal length. The smaller the focal length, the more of your subject you’ll be able to capture in a photograph. That’s why wide-angle lenses have focal lengths ranging from 10-30mm. The focal length number (or range) is found on nearly every camera lens, and is often found next to the lens aperture number.

Lens Diameter

You can use filters on your camera lens to reduce glare or filter out colors to achieve some cool effects. For that, you’ll need to know the lens diameter. It’s measured in millimeters, just like a camera’s focal length, and can be found next to the ø symbol, which represents diameter. The lens diameter is more often than not on the front of the camera lens, or engraved on the side near the top, where you’d screw on your lens filter.

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Automatic or Manual Focus

Automatic focus (relying either on a slower focusing motor or a higher-end, quieter “ultrasonic motor”) lets you keep your subject in focus without manually adjusting the camera’s depth of field yourself. If you see a lens with a switch labeled “AF/MF,” that means you’ll be able to quickly enable the feature—or disable, if you’re going for a particular look in your photographs, or want more control over the image’s depth of field in a controlled environment like a studio.

Brand-Specific Lingo

The more interesting features of a camera lens are often obscured behind brand-specific lingo. Don’t let the acronyms fool you, however. While the abbreviations may vary from camera to camera, the technology behind the features is largely identical.

Optical Image Stabilization

Optical image stabilization is a feature found in both lenses and camera bodies that attempts to counteract vibrations and other tiny movements that could lead to a blurry photo. Image stabilization allows for sharper images, especially when you’re shooting with wider apertures, compared to lenses without image stabilization. Here are the abbreviations you’ll find in these brands:

  • Sony: OSS (Optical SteadyShot)
  • Nikon: VR (Vibration Reduction)
  • Canon: IS (Image Stabilization)
  • Sigma: OS (Optical Stabilization)

Full-frame Sensor Lens

Full-frame cameras use larger, full-frame sensors, which allows for more light to enter the camera and higher-quality photos to be produced. In order to take advantage of the entire sensor, you’ll need a full-frame lens. Some full-frame cameras support cropped lenses, but that cropped lens, designed for a smaller sensor, will result in a photo that uses less of the full-frame sensor’s area. Full-frame lenses are usually more expensive than their cropped lens counterparts. You can read up on the nuances of full-frame cameras and lenses if the thought of higher image quality (and more expensive equipment) appeals to you.

  • Sony: FE (Mirrorless)
  • Nikon: FX
  • Canon: EF
  • Sigma: DG

Cropped Sensor Lens

Cropped sensor cameras are usually found on cameras aimed at consumers or camera enthusiasts. They don’t have the same image quality as a full-frame sensor, but still boast better image quality compared to a device like a smartphone.

How film-based cameras work explained

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In the ongoing saga of film-based versus digital cameras, it is important to understand that one cannot be judged as “better” than the other, despite the passionate opinions of photographers everywhere. They are simply different; one might be more suitable than the other based on subject matter, expertise level, working style and the desired result. Learning the basic differences between the two types of cameras can help a photographer decide which is better suited to the job at hand.

The most obvious difference between digital and film is the ongoing cost of having to buy and develop film. Film photographers are more deliberate with their shooting, whereas digital photographers need not worry about making ten versus a hundred exposures. Still, there are some costs involved in digital as well: higher camera prices, memory cards and possibly image editing software.

Exposure Inversion

Film photographers are taught to “expose for the shadows, develop for the highlights.” For this reason, many photographers have learned to slightly overexpose their film and adjust time in developing. Because digital is a positive image capture, photographers must reverse this rule. Overexposed highlights in a digital image cannot be rectified and erring on the side of underexposure with digital is preferable.

Highlight and Shadow Detail

Many lower-end digital cameras have difficulty capturing details in both shadows and highlights, resulting in black and white blobs. Even cheap film cameras still allow you the option to overexpose to gain shadow detail and then slightly underdevelop to increase highlight detail.

Full-Frame Sensors and Lenses

The focal length of the lens of a digital camera is based on film camera standards. However, because the image sensor has not been traditionally designed to be as large as 35mm film, a 50mm lens on a DSLR (digital single-lens reflex camera) gives a wider angle of view than it would on a film camera. This poses a problem for film photographers with an ingrained knowledge of lens behavior. Newer DSLRs with full-frame sensors address this issue, although these cameras are much more costly than older single-lens reflex cameras.

Chromatic Aberration

Digital photographers must deal with the issue of chromatic aberration more often than film photographers. Digital camera lenses, particularly in point-and-shoot cameras, do not always have the ability to focus all three color wavelengths of light on the same plane. The result is a colored halo around objects in the photo. This effect is seen more often in high-contrast situations and around the edges of the photo. Achromatic and apochromatic lenses help reduce this effect, although these lenses are much more expensive as well.

Chemical Versus Computer Processes

Film camera processing is based on chemistry — on getting hands wet and standing for hours in a darkroom. Using a digital camera results in more time spent in front of a computer screen. These are two very different working processes, both with advantages and disadvantages. Some photographers prefer the physicality of working in the darkroom, while others may want to streamline that process and focus on producing imagery.

How film-based cameras work explained

Tuesday July 3, 2018

How a 360 degree camera works

In short, a 360 camera captures two images or video files from dual lenses with a 180-degree field of view and either automatically stitches them together in-camera, or offers free companion software with which you can stitch the files together – often with one click. In the following guide we’ll demystify some of misconceptions around 360 imaging and explain how 360 cameras work.

360 imaging was once the domain of either well-seasoned professionals working in the cinematic industry or gadget lovers, and few in bestween. But in recent years the launch of 360 cameras like the GoPro Fusion, Garmin VIRB 360, Ricoh Theta V, 360Fly 4K, YI 360 VR and Insta360 ONE have helped bring immersive imaging into the mainstream.

Immersive content once required expensive camera rigs and hours upon hours of editing, but these new breed of 360 cameras brought with them automatic in-camera stitching (apart from GoPro), simpler software and lightweight, portable designs.

And with YouTube and Facebook embracing 360-degree video and images, even more people are beginning to realise the full potential of this recording format. Yet it also remains shrouded in mystery. Exactly how do 360 cameras work? First, let’s tackle that primary misconception…

What’s the difference between 360 and VR?

This is probably the question we hear most often. Are VR and 360 the same? How are they different? People often use the terms 360 and VR interchangeably, but there are a few important distinctions.

The first difference is in the name. Virtual reality means just that: it isn’t real. VR is computer generated content, while 360-degree videos are real life views filmed on wide-angle lenses and stitched together.

And while a 360-degree video is an immersive experience, you are restricted to the camera’s perspective, whether under a waterfall or in the middle of a pizza. In true VR you are free to roam around these virtual environments.

The confusion between 360 and VR comes from people uploading their 360 images and videos to VR headsets. To view 360 videos or images through a VR headset, the content will have been edited with a 3D effect to provide a true immersive experience. Some cameras like the Vuze 3D 360 camera can optimise your content with this effect in-camera. Otherwise, you’ll need 3D editing software.

How film-based cameras work explained

How a 360 camera works: stitching explained

For the purposes of this tutorial let’s talk about consumer 360 cameras like the ones I listed at the start. A consumer 360 camera typically has dual fisheye lenses on either side of the camera’s body. Each of these lenses will offer at least a 180-degree field of view. Typically, it’s a little more. You’ll probably find each lens of your 360 camera captures closer to 200 degrees.

At 400 degrees combined, this, of course, creates some overlap in your footage. The camera (if it stitches in-camera) and software use this overlap to help disguise the seam when stitching your content together.

In most cases, the seam is quite subtle. Where it gets noticeable is when subjects are close to the camera. For instance, if you’re holding the 360 camera on a grip, your hand will likely be split in an awkward angle.

But because most 360 cameras are controlled by companion apps, it means you’re never too far from the camera. This has been one of the Achilles Heels of this nascent technology.

Companies like Insta360, though, have been developing ‘invisible selfie stick’ technology, though, to help minimise these distortions.

360 camera sensors

Like the lenses, 360 cameras employ dual sensors, one behind each lens. Most current models can record at least 4K at 30p. Some 360 cameras, like the Garmin VIRB 360 or YI 360 VR, can record 5.7K footage.

The downside, of course, is that the sensors in 360 cameras are quite small. Also, because your field of view is so wide, dynamic range and exposure can be a problem. Highlights are easily over-exposed and shadow areas lacking in detail. This is because the camera is struggling to create an average exposure from all of that light and dark across the 360 degrees.

Luckily most companion apps offer a modicum of control, with exposure compensation and filters you can apply to improve the exposures.

Recording from your 360 camera

There are typically at least two – and sometimes three, and even four – ways to record video or take still images from your 360 camera. The camera’s body will often have a shutter button for manually taking an exposure. It’s simple, but you’ll probably find that the seam is awkward around your hand.

Most 360 cameras also have a free companion app, and this is where you will want to do the bulk of your shooting. You’ll find all of your exposure controls and even a self-timer, allowing you time to get out of the scene if you wish. Here you’ll also find your options to share content or live stream, if the camera allows it.

Some 360 cameras also offer voice control. The GoPro Fusion and Garmin VIRB 360 both offer this. You can also sometimes buy remote controls for your 360 camera. Others, like the Kodak PixPro 3604KVR include this in the kit.

Framing your 360 shot

Capturing compelling 360 footage is really down to finding a dynamic perspective. While some 360 cameras are limited to mini tripods or plug into your phone, others – like the Garmin and GoPro – are compatible with a wide ecosystem of mounts.

This means you can attach your 360 camera to your bike, head, wrist, car and much more. Your camera’s companion app should also offer a live preview of your scene where you can see what the camera sees and fine-tune accordingly.

The best companion apps will let you swap between lenses and change the default point of view before (and after) recording a 360 video or image.

Other ways to record 360

Dedicated 360 cameras aren’t the only way to create immersive content, but they offer the best compromise between image quality and ease of use.

You can also record 360 videos and images on your smartphone. Your camera app likely has a 360 effect you can utilise by pressing the shutter and manually moving the phone around in a circle to capture the scene.

It’s quite easy to do, but it requires stable hands. And the image quality isn’t the greatest. It’s perfect for sharing with family and friends, though.

The other to record 360 content is to use your interchangeable lens camera. Set your camera up on a tripod, ideally with a fisheye lens. Shoot a frame, rotate, shoot a frame, rotate and keep doing this in a 360-degree circle around your scene. Then tilt the camera up at angle and repeat the process capturing the sky above, and then down to capture the ground.

You’ll then need to process your images which you can do in Photoshop, or via a dedicated panorama stitching software. Using a DSLR or mirrorless camera takes more time, but the level of detail and image quality you’ll capture will be far superior.