types of camera

Animation camera

An animation camera is a type of rostrum camera. They are specially adapted for frame-by-frame shooting animation or stop motion. They consists of a camera body with lens and film negotiates. New animation cameras are not widely manufactured. Image scanners, video cameras and DSLRs have taken their place.

Autofocus camera

An automatic focus camera uses a sensor, a control system, and a motor or turntable optical element to focus automatically or a manually selected point. An electric rangefinder is displayed instead of the motor. Automatic focus methods are distinguished by their type as being active, passive or hybrid variants.

Banquet camera

A Banquet camera is a type of large format camera that was used in the early 20th century for photographing large groups of people at formal occasions.

Bridge camera

Bridge cameras are cameras that fill a niche between the single-lens reflex camera and the point-and-shoot camera. They are often comparable in size and weight to the smallest DSLRs. There are also Superzoom DSLR shaped bridge cameras with a retractable lens to make it more compact. A lot of them lack an optical viewfinder system. They normally feature interchangeable lenses and are prominent in the prosumer market segment. The phrase has been in use since the 1980’s and continue to be used with digital cameras. The term was originally used to refer to film cameras which bridged the gap between the point and shoot cameras and DSLRs. Most of them are digital. They feature full manual controls over the shutter speed, aperture, ISO sensitivity, colour balance and metering. They also feature sets that are similar to consumer DSLRs, except for their smaller range of ISO sensitivity because of the smaller image sensor. Many of them have long zoom lenses that start at a wide angle focal length of 20 or 22mm. The term is often often used interchangeably with megazoom. Some of them only have moderate or short zooms, whilst compact cameras have super zoom lenses but lack the advanced functions.

Camcorder/professional video camera

A camcorder/professional video camera is an electronic device combining a video camera and a video recorder.  The term is used to describe a portable, self-contained device with video capture and recording as its primary functions. The earliest types were tape based and recorded analogue signals and videotape cassettes.  Digital recording had become normal in the 21st century, with the tape being replaced by  storage media such as internal flash memory and SD cards. The term was used to refer to a camera with a recorder but camcorder that are built in the 21st century provide recording capability essentially making them a camcorder. The term is now used for a particular camera range that provides the advanced functions over more common cameras.

Professional cameras have very few automatic functions. Their operators would normally not use automatic focus or an automatic iris. The zoom feature moves your point of view closer to, or further away from the subject. This is similar to moving the camera closer or further away from the subject. Professional video cameras normally have a focus ring at the front of the lens housing. To do this they have to be turned clockwise for a closer focus, or anti-clockwise for a more distant focus. They also have an iris ring on the lens housing, in which when you turn it clockwise it closes, and when you turn it anti-clockwise it opens. They also have a white balance function, which means colour balance. The white balance tells the camera what each of the colours should look like. It is normally done automatically by consumer-level cameras without the operator being aware. It works well in most situations, but there are some conditions that the automatic white balance will not like. This is where the colours will seem wrong or unnatural.  To do a white balance, we have to point the camera at something that is plain white (for example a sheet of paper), in the same light as the subject and frame it so that the white object covers the screen. We then need to set the focus and exposure, then press the white balance button. In the viewfinder, there should be an indicator that tells you when it is white.

High frame camera

A high frame camera is capable of image exposures in excess of 1/1000 or frame rates in excess of 250 frames per second.  They are used for recording fast-moving objects as photographic images onto a storage medium. After recording, the images that are stored on the camera can be played back in slow-motion. Early high speed cameras had used film to record high speed event, but now, they are completely electronic using either a charged coupled device or a CMOS active pixel sensor and records over 1,000 frames per second into the DRAM and play images back slowly to study the motion for the study of transient phenomena. They can be classified as a high speed camera that records film, a high speed camera that records a short burst of high frame rate images to film or a network of CCD cameras, a high speed streak camera that records a series of line sized images to film or electronic memory.

Camera phone

A camera phone is a mobile phone that is able to capture photographs and record videos. The first one was sold in Japan in the year of 2000 and was a J-phone model, and was released about a decade after the first digital camera was sold in Japan in December 1989. Most of them are easier to use than digital cameras. Their usual fixed-focus lenses and small sensors limit their performance in poor lighting. Some have a long shutter lag and their flash is usually weak. Optical zoom and tripod screws are rare. Some can also lack a USB connection or a removable memory card. Most of them now have bluetooth and wifi and can make geotagged images. Some of the more expensive ones have a few technical disadvantages, but with bigger image sensors, their capabilities approach the low-end point-and-shoot-cameras. In the smartphone era, the sales increase of camera phones caused a point-and-shoot camera sales to peak in 2010 and decline thereafter. Most model lines have improved their cameras. Some only have a menu choice to start the camera application, others have separate camera buttons. Few of the are designed to resemble low-end digital compact cameras in their appearance and in the feature and picture quality, and they are branded as both mobile phones and cameras. Their principle advantages are the cost and compactness. They may run mobile applications to add capabilities such as geotagging and image stitching. High end phones can use their touch screen to direct their camera to focus on a particular object in the field of view, giving an inexperienced user a degree of focus control that is exceeded by seasoned photographers using manual focus. The touch screen, may lack the agility of a separate camera’s dedicated buttons and dial.

Closed-circuit television camera

• also known as CCTV
• produces images or recordings for surveillance purposes
• can also be video game, or digital still cameras
• invented by Marie Van Brittan Brown

Compact camera

• still camera that is designed for simple operation
• Most of them use focus free lenses or autofocus for focusing, automatic systems for setting the exposure options, and have flash units built in
• best selling type of separate camera
• popular with people who don’t consider themselves photographers but want a camera that is easy to use to take snapshots of events that they want to remember, for example holidays, parties, reunions, and other events
• sales in this type of camera had declined after the year of 2010 as smartphones had overtook them for the same uses
• now, manufacturers boost the travel superzoom compact cameras with optical zoom up to 30x with a weight of 300 grams or less than a bridge camera or DSLR weighs
• prioritise intelligent auto, but some advance cameras have PSAM dial, RAW, and hotshoe, but nobody has a lens thread

Compact System cameras

• Interchangeable cameras that do not have a mirror reflex optical viewfinder
• a subset of interchangeable lens cameras, which is a category that also includes single lens reflex cameras
• designed to have the advantage of having a smaller size, a lighter weight, and a lower cost than DSLRs, which still allowing us to swap lenses
• comprised of 5% of total camera shipments in 2013
• this year, they accounted for 26% of interchangeable lens camera sales outside of america, but only 16% in america
• available with a mixture of sensor sizes
• when the sales of DSLRs had fell in 2013, many manufacturers had responded by releasing many of this type of camera, including the lenses

Dashcam

• onboard camera that attaches to a vehicles window screen
• can also be positioned on the top of the dashboard or rear view mirror using a mount
• records what is in front of the vehicle whilst it is in motion
• can provide video evidence of an accident
• various types are available
• most are manufactured in Asian countries such as China and Taiwan

Digital camera

• encodes digital images and videos digitally and stores them for later reproduction
• most cameras that are sold now, are digital
• are incorporated into devices ranging from PDA’s and mobile phones to vehicles
• shares an optical system with film cameras, using a lens with a variable diaphragm to focus the light onto an image pickup device
• diaphragm and shutter emit the correct amount of light to the imager, just like it does with film, but the image pickup device is electronic rather than chemical
•  can display images on screen immediately after being recorded, and store and delete images its memory
• many can also record moving images with sound
• some can also crop and stitch pictures and perform other basic image editing

Disposable camera

• box camera sold with roll of film installed
• are only to be used once
• most use fixed focus lenses
• some may be equipped with an integrated flash unit
• are waterproof versions for underwater photography
• use a 135 film or APS cartridge
• some contain a cartridge that is used for loading normal, reusable cameras
• some have the film wound internally on an open spool
• The whole camera is then taken for processing
• some of the cameras are recycled

Document cameras

• real time image capturing devices that are used for displaying objects to a large audience
• are able to magnify and project images of 3D objects
• are high resolution webcams, mounted on arms so that they can facilitate their placement over a page
• objects can be displayed by a document camera
• most objects are placed under the camera
• the camera can take a picture of the object which produces a live picture using a projector
• different types of this camera allow great flexibility in terms of the placement of the objects
• larger objects, can be placed in front of the camera and the camera will be rotated as necessary, or a ceiling mounted document camera can be used to allow a larger working area to be used
• they can be fused for: lecture hall or classroom use, to present material in conferences, meetings and training sessions, video conferencing and telepresence, to present evidence in courtrooms, various medical applications

Field camera

• view camera that can be folded into a compact size
• modern designs are different from the first folding field cameras from the 19th century
• have more limited camera movements than monorail cameras, but are comparatively compact and portable when they are folded
• Modern ones originate from the early interlocking cameras from the 19th century
• substitute bellows to reduce the bulk of the cameras and make them easier to use outside rather than in a studio
• modern ones tend to have the most camera movements for the front standard, but are more limited in back movements
• normally use sheet film
• normally used by photographers who need the larger negative sizes and the portability

FireWire camera

• use an IEEE 1394 bus standard for the transmission of audio, video and control data
• apple computer’s trademark for the IEEE 1394 bus standard
• available in the form of photo cameras and video cameras that provides image and audio data
• a special form of video camera that is used in the domains of industry, medicine, astronomy, microscopy and science
• these cameras don’t provide audio data

Folding camera

• derive their name from their feature that they are folded into a compact and rugged package for storage
• camera objective sits attached to a bellows
• inside the bellows is a pantograph style mechanic that attaches the object to the body
• when the camera is totally unfolded, it can provide the correct focus
• the advantage of these cameras is that they have an excellent physical-size-to-film-size ratio when the camera is folded for storage
• this feature can have an advantage when filming large physical films
• dominated camera design from the 1900’s to the 1940’s
• their use was declined after World War II after the introduction of 35mm film in the consumer market

Gun camera

• used in aircraft to help measure tactical effectiveness
• are triggered by the firing of a weapon
• first became common for gunnery training in the 1920’s but examples were used during world war I by the British Royal Flying Corps
• special version of the Lewis Machine gun was manufactured as a camera gun
• during world war II, they were used on operation aircraft to record kills of enemy aircraft
• some footage has survived and is often the source for stock footage in world war II movies, TV shows or video games
• term guncam can also refer to software that records video game footage, which can be triggered by the firing of a weapon in a way that is similar to the original guncams of world war II
• some examples of this software are Growler Guncam and Java Guncam
• may also refer to a video camera that is mounted on a gun where the camera has a point of aim indicator, which is typically a reticle in the form of a crosshair or a red dot, which shows in the video where the gun is being pointed

Helmet camera

• attached to a helmet
• allows us to make a visual record from our point of view, whilst keeping our hands and vision free

 

Hidden camera

• still or video camera that is used to film people without them knowing
• it is hidden because it is either not visible to the subject that is being filmed, or is disguised as another object
• can be built into commonly used objects like television sets, smoke detectors, clock radios, motion detectors, ball caps, plants and mobile phones
• may be used for household surveillance and also commercially or industrially as security cameras
• the expansion and lower costs of video recording devices has led to an increase in the use of hidden cameras for surveillance needs, as well as entertainment and other purposes
• their use raises privacy issues
• may be legal aspects to consider, depending on the control that takes place
• can be contrasted with CCTV, which is visible and is sometimes accompanied with a warning notice of its presence

Instant camera

• uses self developing film to create a chemically developed print after taking the picture
• their invention was credited to scientist Edwin Land, who had unveiled the first commercial instant camera in 1948, which was a year after unveiling instant film in New York City
• earliest instant camera was invented in 1923 by Samuel Shlafrock

IP camera

• type of digital video camera used for surveillance, and can send and receive data through a computer network and the internet
• but, most of these cameras are webcams
• term is applied only to those that are used for surveillance
• two kinds of IP camera: Centralised-require a central Network Video Recorder to handle the recording, video and alarm management, Decentralised-do not require a central Network Video Recorder, as they have a recording function built-in and can record directly to any standard storage media, such as SD cards, NAS or a PC/server

Slow motion Camera

• standard speed for cinematic pictures is 24 frames per second
• This can create a fluid movement for each of the frames and is fast enough to trick our brains into thinking that what we are seeing are moving but slow enough to let us know that it is all fake
• can be shot at a higher frame, such as the following youtube clip which is shot at 240 frames per second

http://www.makeuseof.com/tag/slow-motion-video-work-can-shoot/

• the rule of frame rates is that the denominator of the shutter speed should be double the frame rate
• For example, if the frame rate was at 24 frames per second, the denominator should be at 1/48
• This is very easy to do when using a DSLR or high-end video camera
• For slow motion video, we can shoot at 48 frames per second, which means that the denominator should be 1/96

Lens focal length

The focal length of a lens is normally represented in millimetres and is the basic description of a photographic lens. It is not at all the measurement of the actual length of the lens, but an estimate of the optical distance from where the light rays cover to form a clear image of a subject to the digital sensor or 35mm film at the focal plane in the camera. It is determined when the lens is focused at infinity.

It tells us the angle of the view, how much of the scene will be captured and the magnification. The longer that the focal length is, the more limited the angle of view will be, and the higher the magnification. Which also means that, the shorter the focal length, the wider the angle of view will be, and the lower the magnification.

Zoom lenses

A zoom lens has variable focal lengths. An advantage of a zoom lens is it’s versatility. They are ideal when taking photos of a variety of subjects and reduce the number of times you need to change the lens which can save time and limits the possibility of getting dust in the camera’s mirror box or on the sensor.

macro lenses

These lenses should be able to copy a life-size image of an object on the recording medium. They can offer a magnification factor of 1.0x or 1:1 at it’s closest focus setting. You can get very good enlargements of objects using a macro lens that only offers 0.5x maximum magnification.

• 0.2x: At the bottom of these lenses, some of them only give an image on the sensor that is a fifth of the size, when it is focused as close as possible
• 0.34x: Some lenses do better and produces an image that is one-third of the life-sized object shot at the minimum focus level
• 0.5x: these lenses offer half the size of the image
• 1.0x: produces a life-sized image on the sensor when it is focused as close as possible
• 5.0x: gives a bellows like magnification, giving images on the sensor that are up to five times the size

One feature of macro lenses is that they are “flat field” lenses. As general lenses suffer from field curvature, the point of focus would be a different distance towards the corners of the frame compared to the centre.

Wide angle lenses

A wide angle lens is where the focal length is a lot smaller than the focal length of a normal lens for a given film plane. It allows more of the scene to be included in the image. It is useful in architectural, interior, landscape photography. But, the photographer may not be able to move further from the scene to photograph it. The photographer can also wish to emphasise the difference in size or the distance between objects in the foreground and background. This exaggeration can be used to make the foreground objects more noticeable and impressive whilst capturing expansive backgrounds. They protect a larger image circle than the typical standard for a design lens of the same focal length which enables either large tilt and shift movements with a view camera or a wide field of view. In still photography, a normal lens for a specific format has a focal length that may be equal to the length of the diagonal of the image from or digital photosensor. In cinematography, the lens is normally double the size of the diagonal.

Normal lenses

Normal lenses reproduce a field of view that looks natural to the human observer under normal viewing conditions, as compared to lenses that have either longer or shorter focal lengths that produce an enlarged or developed field of view that distorts the perspective when viewed from a normal viewing distance. Lenses that have a shorter focal length are called wide angle lenses, whilst longer focal length lenses are called long-focus lenses. In still photography, a lens with a focal length that is equal to the size of the film or sensor format is considered to be a normal lens as its angle of view is similar to the angle that is subtended by a large print that is viewed at a typical viewing distance that is equal to the print diagonal. In cinematography, where the image is viewed at a bigger distance, a lens with a focal length of double the film or sensor diagonal is considered normal. The term can also be used as a synonym for a rectilinear lens.

Telephoto lenses

Telephoto lenses are a set type of long focus lenses in which the length of the lens is shorter than the focal length, which is achieved by including a lens group that is known as a telephoto group that makes the light path bigger to create a long focus lens in a smaller design. The angle of view and other effects of long focus lenses are the same specified focal length. Long focal length lenses are often referred to as telephoto lenses even though this is incorrect, a telephoto lens is incorporated in the telephoto group. They are sometimes broken into further subtypes. These are:

• Medium telephoto: lenses that cover between 30 degrees and 10 degrees of the field of view
• super telephoto: lenses that cover between 8 degrees through a 1 degree field of view

Lens structure

Lens structure is the design for use in still or cine cameras that is intended to construct a lens that gives the most acceptable performance of the subject that is being photographed within a range of restrictions that can include cost, weight, and materials. For a lot of other devices, such as telescopes, microscopes and theodolite where the visual image if noticed but often not recorded, the design can can be more straightforward than os the case in a camera where ever image is recorded on film or image sensor and can be subject to detailed inspection at a later stage. Photographic lenses also include those in enlargers and projectors.

Depth of field

The depth of field is also called the focus range or effective focus range. It is the distance between the nearest and furthest objects in scenes that appear very clearly in an image. They can exactly focus on only one distance at a time, but the decrease in sharpness is gradual on each side of the distance, so that within the depth of field, the unsharpness is unnoticeable under normal viewing conditions. It may be desirable to have an entirely sharp image, and a large depth of field is allowed. In other cases, a small depth of field may be more effective, emphasizing the subject whilst de-emphasizing the foreground and background. In cinematography, a large depth of field is called a deep focus, and a small depth of field is often called a shallow focus.

F-numbers

F-numbers are a combination of two terms. F/N is the concept that is used to indicate the size of the diaphragm opening, or the aperture, in a camera. Aperture openings can be measured as fractions of the focal length of a lens. The f, stand for focal length, in the aperture rating. Supposing that we had the definitive example of lenses, the 50mm, with an aperture of f/2.8, we can find out the diameter of the aperture opening like this:

• 50mm/2.8=17.85mm

If we open the aperture to maximum, it would be measured at:

• 50mm/1.4=35,71mm

The difference between the aperture of f/2.8 and the aperture of f/1.4 is a contrast of four times as much light. This is because the area of aperture opening is four times as big at f/1.4 as it is at f/2.8. A stop in photography nomenclature means that there is a difference of one exposure value, which is the double, or halving of the amount of light that is reaching the sensor. These are standard full stops that f-stops are rated in: 1, 1.4, 2, 2.8, 4, 5.6, 8, 11, 16, 22, 32, 45, 64. Here is an example of an f-number scale:

 

These settings all differ by one exposure value, or a full stop, and create a full f-stop scale. When we close down the 50mm f/1.4 lens from the maximum aperture of f/1.4 to an aperture of f/2.8, we are stopping down by two full stops. It has to be noted that a lot of cameras offer two additional f-stop scales beyond what is the standard full stop scale:

• A half-stop scale
• A third-stop scale

A lot of cameras default to a fractional scale rather than the full stop scale, this is why it is important to learn and memorize the full stop scale so that proper adjustments are made when changing the aperture setting on the camera.

There is an important relationship between the aperture and the shutter speed, as they are both rated in stops. Whilst the aperture is denoted in f-stops, the shutter speed changes are called stops or exposure values.

Diffraction limits

Diffraction is an effect that limits the resolution of photography. It happens because light starts to spread when passing through a small opening.  It is normally insignificant, since smaller apertures often improve the sharpness by minimising lens aberrations. But, this method becomes counterproductive. Knowing this can help maximise the detail, and help avoid long exposures or high iso speeds that are unneeded. Light rays that are passing through a small aperture will begin to separate and obstruct with each other.  This can become more important as the size of the aperture decreases relative to the wavelength of the light that is passing through,  but it occurs to some extent for any aperture or intense light source.  Since divergent rays now travel in different distances, some move out of the phase and begin to interfere with each other.  This produces a diffraction pattern with top strengths where the amplitude of the light waves add, and less light where they subtract. If we were to measure the power of light reaching all of the positions on a line, these measurements would appear as bands.

For the ideal circular aperture, the 2-D diffraction pattern is called an airy disk, after it’s discoverer George Airy. The width of it is used to define the theoretical maximum resolution for an optical system. When the width of it’s central peak becomes largely relative to the pixel size in the camera, it will begin to have a visual impact on the image. Once they become any closer than half of their width, they are no longer resolvable.

Diffraction sets a basic resolution limit that is individualistic of the amount of megapixels, or the size of the film format. This depends on the f-number of the lens that is being used, and the wavelength of the light that is being seen. We can think of it as the smallest theoretical pixel of detail in photography. additionally, the beginning of diffraction is slow, prior to limiting the resolution, it can reduce the small-scale contrast by causing the airy disks to partially overlap. The size of the airy disk is practical in the context of the pixel size. As the result of the sensor’s anti-alising filter, the airy disk can have a diameter of 2-3 pixels before the diffraction limits the resolution. But, diffraction may have a visual impact prior to reaching the diameter. For example, a canon EOS 20D begins to show diffraction at f/11, whereas the canon Powershot G6 begins to show the effects at only f/5.6. Furthermore, the canon G6 does not need apertures that are as small as the 20D in order to achieve the same depth of field, due to a much smaller sensor size. Since the size of the disk can also depend on the wavelength of the light, each of the primary colours will reach its diffraction limit at a different aperture. When the lens aperture is at, for example, f/16 and the airy diameter is at 21.3m, it assumes that the light is in the middle of the visible spectrum.

A typical DSLR camera captures light with a wavelength of anywhere between from 450 to 680nm, so at best, the disk would have a diameter of 80%. Another complication is that sensors that utilize a bayer array can allocate twice the fraction of pixels to green as red or blue light, and then introduce these colours to produce the final full colour image. This can mean that as the diffraction limit is near, the first signs will be a loss of resolution in green and pixel-level luminosity. The blue light requires the smallest of apertures in order to reduce it’s resolution due to diffraction.

Only real world photography can show its visual impact. Even when the camera system is near or just past it’s diffraction limit, other factors such as focus accuracy, motion blur and imperfect lenses are more likely to be significant. Therefore, diffraction limits the total sharpness only when using a solid tripod, a mirror lock-up and a very high quality lens. Some diffraction can be good if you are willing to sacrifice sharpness at the focal plane in exchange for sharpness outside of the depth of field. On the other hand, very small aperture can be required to achieve long exposures, such as to induce a motion blur with flowing water. This means that diffraction is something to be aware of when choosing the exposure settings, similar to how we balance the other trade-off’s such as noise vs the shutter speed. This does not mean that larger apertures are better, although very small apertures create a soft image, most lenses are also soft when they are used wide open.

Camera systems have an optimal aperture that is in between the largest and smallest settings and with most lenses the optimal sharpness can be closer to the diffraction limit, but with some lenses this may occur prior to the diffraction limit. These calculations only show when the diffraction becomes significant, not the location of the optimum sharpness. This does not mean that the smaller pixels are worse, as both of the scenarios still have the same total resolution. But, the camera with smaller pixels will render the image with less artefacts. Smaller pixels can also give more creative flexibility, since they can yield a higher resolution when using a larger aperture in possible. Additionally when the other factors like noise and dynamic range are considered, the small vs large pixels debate becomes more complicated.