Digital versus film photography wikipedia

film vs digital

1. Digital versus film photography has been a topic of debate in the photography world, as well
as the film industry since the availability of digital cameras towards the end of the 20th Century.
Both digital still photography as well as digital cinematography versus film and motion picture
film photography have advantages and drawbacks.
[1][2]
21st century photography is now
dominated by digital operation, but the older photochemical methods continue to serve many
users and applications.
Image quality[edit]
Spatial resolution[edit]
The quality of digital photographs can be measured in several ways. Pixel count is presumed to
correlate with spatial resolution.
[3]
The quantity of picture elements (pixels) in the image sensor is
usually counted in millions and called "megapixels" and often used as a figure of merit. Digital
cameras have a variable relationship between final output image resolution and sensor
megapixel count.
[4]
Other factors are important in digital camera resolution, such as the number
of pixels used to resolve the image, the effect of the Bayer pattern or other sensor filters on the
digital sensor and the image processing algorithm used to interpolate sensor pixels to image
pixels. Digital sensors are generally arranged in a rectangular grid pattern, making images
susceptible to moire pattern artifacts, whereas film is not affected by this because of the random
orientation of its grains.
[5]

The resolution of film images depends upon the area of film used to record the image (35
mm, Medium format or Large format) and the speed. Estimates of a photograph's resolution
taken with a 35 mm film camera vary. More information may be recorded if a fine-grain film,
combined with a specially formulated developer, are used. Conversely, use of poor quality optics
or coarse-grained film yield lower image resolution. A 36 mm x 24 mm frame of ISO 100-speed
film was initially estimated to contain the equivalent of 20 million pixels,
[6]
although this estimate
was later revised to between 4 and 16 million pixels depending on the type of film used.
[7]

Many professional-quality film cameras use medium format or large format films. Because of the
size of the imaging area, these can record higher resolution images than current top-of-the-range
digital cameras. A medium format film image can record an equivalent of approximately 50
megapixels, while large format films can record around 200 megapixels (4 × 5 inch) which
equates to around 800 megapixels on the largest common film format, 8 × 10 inches, without
accounting for lens sharpness.
[8]
Medium format digital provides from 39 to 80 megapixels.
Thus film and digital work each provide a wide range of performance in this regard, overlapping
but with film tending to higher resolution. Resolution of both film and digital are subject to the
quality of lens fitted to the camera. The medium which will be used for display, and the viewing
distance, should be taken into account. For instance, if a photograph will only be viewed on an
old analogue television that can resolve approximately 0.3 megapixel or modern HDTV set
of 1080p with 2 megapixels, the resolution provided by high-end camera phones may suffice,
and inexpensive compact cameras usually will. Similar or more expensive hardware may also fill

2. the screens of computer displays, though those few that show tens of megapixels is currently out
of reach of low-end film photography and all but specialized scientific or industrial digital
cameras.
Noise and grain[edit]
Thermal noise, produced by heat and manufacturing defects, degrades shadow areas of
electronic images with random pixels of the incorrect color. Film grainbecomes obvious in areas
of even and delicate tone. Grain and film sensitivity are linked, with more sensitive films having
more obvious grain. Likewise, with digital cameras, images taken at higher sensitivity settings
show more image noise than those taken at lower sensitivities.
[6]

However, even if both techniques have inherent noise, it is widely appreciated that for color,
digital photography has much less noise/grain than film at equivalent sensitivity, leading to an
edge in image quality.
[9]
For black-and-white photography, grain takes a more positive role in
image quality, and such comparisons are less valid.
Noise is a particularly critical issue with digital cameras, often producing color distortion or
confetti, occurring most severely on the blue component and least severely on the red
component. Nearly all digital cameras apply noise reduction to long exposure photographs to
counteract thermal noise. For very long exposures, the image sensor must be operated at low
temperatures to prevent noise affecting the final image. Film grain is not affected by exposure
time, although the apparent speed of the film changes with lengthy exposures, a phenomenon
known as reciprocity failure.
Autofocus and auto exposure systems[edit]
In regards to compact cameras, digital compact cameras have the advantage of using face
detection or contrast detection on the actual image captured. This is significantly more
advantageous than compact film cameras that use active infrared autofocus systems which then
estimate the lens position. Similarly exposure levels can be detected directly from the image
sensor rather than through another light meter used in film cameras. On the budget end of the
scale, digital compact cameras tend to give better image quality than their budget film
counterparts due to these more superior focusing and exposure mechanisms.
Dynamic range[edit]
Dynamic range is a complex issue.
[10]
Comparisons between film and digital media should
consider:
 Film type: For example, low-contrast print film has greater dynamic range than slide film's
low dynamic range and higher contrast.
 Data format: Raw image format or lossy compression.
 Pixel density of the sensor: The large sensors in DSLRs and medium format digital
cameras generally have larger photosites which collect more light and therefore are
generally more sensitive than their diminutive counterparts in compact digital cameras. The

3. larger sensors tend to have better signal to noise characteristics. However signal processing
and amplification improves with generation and small sensors of today approach the
dynamic range of large sensors in the past.
 Scanner: Variations in optics, sensor resolution, scanner dynamic range and precision of the
analogue to digital conversion circuit cause variations in image quality.
 Optical versus digital prints: Prints differ between media and between images shown
on Visual display units.
 Signal/noise ratio: This defines the limits of dynamic range within a single photograph, and
may vary with subject matter. A single comparison cannot demonstrate that digital or film has
a smaller or greater dynamic range.
Dynamic range is of considerable importance to image quality in both the digital and emulsion
domain. Both film and digital sensors exhibit non-linear responses to the amount of light, and at
the edges of the dynamic range, close to underexposure and overexposure the media will exhibit
particularly non-linear responses. The non-linear dynamic response or saturation qualities of
emulsion film are often considered a desirable effect by photographers, and the distortion of
colour, contrast and brightness varies considerably between film stocks. There is no limit to the
number of possible levels of colour on emulsion film, whereas a digital sensor stores integer
numbers, producing a limited and specific possible number of colours. Banding may be visible in
the unusual case that it is not obscured by noise, and detail may be lost, particularly in shadow
and highlight areas.
According to Eastman Kodak in 2007, digital sensors of the time lacked the extended dynamic
range of film. In particular, they tend to 'blow out' highlights, losing detail in very bright parts of
the image.
[11]
If highlight detail is lost, it is nearly impossible to recapture in post-
production.
[12]
Therefore, film can be underexposed and overexposed, retaining detail and
information in the camera negative.
[11]

Some amateur authors have performed tests with inconclusive results. R. N. Clark, comparing a
professional digital camera with scans of 35 mm film made using a consumer level scanner,
concluded that "Digital cameras, like the Canon 1D Mark II, show a huge dynamic range
compared to [scans of] either print or slide film, at least for the films compared."
[13]

Carson Wilson informally compared Kodak Gold 200 film with a Nikon D60 digital camera and
concluded that "In this test a high-end consumer digicam fell short of normal consumer color print
film in the area of dynamic range."
[14]

The digital camera industry is attempting to address the problem of dynamic range. Some
cameras have an automatic exposure bracketing mode, to be used in conjunction with high
dynamic range imaging software. Some CCDs including Fujifilm's Super
CCD combine photosites of different sizes to give increased dynamic range. Other
manufacturers use in-camera software to prevent highlight overexposure. Nikon calls this
feature D-Lighting.

4. Presentation technology is also relevant, as different color printing methods, cathode-ray
tubes, LCDs and other displays all have different dynamic range limits and degrees of linearity.
Effects of sensor size[edit]

Drawing showing the relative sizes of sensors used in most current digital cameras.
Almost all compact digital cameras, and most digital SLRs or ILCs, have sensors smaller than
the 36 mm x 24 mm exposure-frame of "35 mm" film. The smaller sensors found in DSLR
cameras affect:
[15]

1. Depth of field;
2. Light sensitivity and pixel noise;
3. Relative cropping of the field of view when using lenses designed for 35 mm camera;
4. Optimizing lens design for smaller sensor area;
5. Increased relative enlargement of the captured image.
Depth of field is often quoted as being greater for digital cameras than for film cameras. The
maxim packages several counterintuitive aspects of photography into a single (largely correct)
theorem. Depth of field, for a given lens focal length, at a given f-number will scale with
sensor (film/chip) size. In effect, a smaller sensor will increase the apparent depth of field
because it magnifies the portion of the image that is in focus.
Manufacturers are increasingly using (especially in the budget digital camera market) "35
millimeter equivalent" focal lengths for lenses. This gives rise to the "depth of field is greater for
digital cameras" myth: the shorter the focal length of a lens, the greater is its depth of field (at
fixed F-stop). Therefore, if a sensor that is one-fourth the width and height of a 24 x 36 mm frame
of film is exposed to an image through a lens that is correspondingly one-fourth the focal length,
the depth of field increases 16x (scaling per the square of focal length) on an absolute scale, but
4x from a comparison-of-images perspective (the imaging dimension is 4x smaller).
This increase in relative depth-of-field may have advantages for taking snapshots; more image
will be in focus than with a larger sensor and autofocus system accuracy is less critical for
producing an acceptable image. Contrarily, photographers wishing to decrease depth of field to

5. create certain effects, such as isolating subjects from their background need to increase
aperature for sensors smaller than 36 mm x 24 mm to achieve the same degree of selective
focusing.
[16]
Depth of field can be minimized by use of large format cameras, which are very rarely
digital.
Light sensitivity and pixel noise are both related to pixel size, which is in turn related to sensor
size and resolution. As the resolution of sensors of a specific format increases, the size of the
individual pixels naturally has to decrease. This smaller pixel size means that each pixel collects
less light and the resulting signal must be amplified more to produce the final value. Noise is also
amplified and the signal-to-noise ratio decreases, and the higher noise floor means that less
useful information is extracted from the darker parts of the image.
[15]
Countering these effects of
digital-signal noise are advances being made in sensor technology itself. As of 2012, the top-end
of digital sensor sensitivity is at ISO 204,800 (in both Canon and Nikon DSLRs), whereas less
expensive prosumer DSLR and ILC cameras offer sensitivities up to ISO 6400 or even higher,
often with good noise performance at one-quarter maximum sensitivity. In recent years larger
sensor digital compacts have become available. However, they still are bigger and heavier than
the smallest 35mm cameras and are not full frame.
Some digital SLRs use lens mounts originally designed for film cameras. If the camera has a
smaller imaging area than the lens' intended film frame, its field of view is cropped. This crop
factor is often called a "focal length multiplier" because the effect can be calculated by multiplying
the focal length of the lens. For lenses that are not designed for a smaller imaging area whilst
using the 35 mm-compatible lens mount, this has the beneficial side effect of only using the
centre part of the lens, where the image quality is in some aspects higher.
[c itation needed]
Only
expensive digital SLRs and very rarely expensive 'compacts' have 36mm × 24 mm sensors,
eliminating depth of field and crop factor problems when compared to 35 mm film cameras.
[c itation
needed]

In compact digital cameras, the size of the sensor is often several times smaller than the
standard 36 mm x 24 mm film, with the area being typically 20 to 40 times less than that of a
frame of film.
[17]
This difference gives film compacts a substantial advantage when it comes to
image quality and the ability to take pleasing portraits. In the standard consumer market film's
advantage over digital in the compact market is often negated by operator error, the generally
poor quality of the cameras or because of poor quality processing of films. The smaller sensor
size of digital compact cameras means that prints are extreme enlargements of the focused
image, and that the lens must perform well in order to provide enough resolution to match the
tiny pixels on the sensor.
To manufacturers, large lenses are very costly to produce, smaller sensors in digital cameras
enable the use of smaller and more compact arrangement of lenses. Affordable superzooms
cameras that can magnify images 50-60 times are now available. These kinds of magnification
are virtually impossible to achieve in 35mm film cameras. Compact cameras such as the Lumix
LX-7 with a maximum aperture of f/1.4 is achievable with smaller sensors.

6. Convenience and flexibility[edit]
Flexibility and convenience are among the reasons for the widespread adoption of digital
cameras. With film cameras, a roll is usually completely exposed before being processed. When
the film is returned it is possible to see the photograph, but most digital cameras incorporate
a liquid crystal display that allows the image to be viewed immediately after capture. The
photographer may delete undesired or unnecessary photographs, or reshoot the image if
required. A user who wants prints can quickly and easily print just the required photographs.
Photographic film is made with specific characteristics of Color temperature and sensitivity (ISO).
Lighting conditions often require characteristics different from those of the film specifications,
requiring the use of filters or corrections in processing. Digital photography allows color
temperature and sensitivity to be adjusted at each shot, either manually or automatically.
Digital images may be conveniently stored on a personal computer or in off-line storage such as
small memory cards. Professional-grade digital cameras can store pictures in a raw image
format, which stores the output from the sensor rather than processing it immediately to form an
image. When edited in suitable software, such as Adobe Photoshop or the GNU
program GIMP (which uses dcraw to read raw files), the user may manipulate certain
parameters, such as contrast, sharpness or color balance before producing an
image. JPEG images can be similarly manipulated, though usually less precisely; software for
this purpose may be provided with consumer-grade cameras. Digital photography allows the
quick collection of a large quantity of archival documents, bringing convenience, lower cost and
increased flexibility in using the documents.
[18]

Modern film cameras are not as power thirsty as modern digital cameras, and can last longer on
smaller batteries. Some film cameras, especially older ones, can operate without batteries: some
will function completely without batteries while others may lose some functionality such as
metering and some shutter speeds. Batteries that only have to power light meters are often very
small and can last a long time. This can be a boon for those who may be spending a long time
with little or no access to power. Film cameras may also be carried as backups for this reason.
For large format and ultra large format photography, film may have some advantages over digital
cameras, such as price and flexibility, when used outside the studioenvironment. Digital rotating
line cameras provide similarly high performance, but scan mechanically rather than use a single
sensor. Thus they cannot scan anything that moves, and are expensive, large, and rarely moved.
Film speed[edit]
Digital cameras are capable of much higher speeds (sensitivities) than film, can perform more
desirably in low light situations at night or indoors, and are more useful for ultra-fast photography.
In addition, on digital cameras the speed can be adjusted at any time, while a film camera
requires changing the film to change the film speed.
Cleanliness[edit]

7. Dust on the image plane is a constant issue for photographers, and especially so in digital
photography. DSLR cameras are especially prone to dust problems because the sensor remains
in place, whereas a film advances through the camera for each exposure. Debris in the camera,
such as dust or sand, may scratch the film; a single grain of sand can damage a whole roll of
film. As film cameras age, they can develop burs in their rollers. With a digital SLR, dust is
difficult to avoid but is easy to rectify using a computer with image-editing software. Some digital
SLRs have systems that remove dust from the sensor by vibrating or knocking it, sometimes in
conjunction with software that remembers where dust is located and removes dust-affected
pixels from images.
[19]

Compact digital cameras are fitted with fixed lenses, which makes it harder for dust to get into
the image area. Similar film cameras are often only light-tight and not environmentally sealed.
Some modern DSLRs, like the Olympus E-3, incorporate extensive dust and weather seals to
avoid this problem.
Integrity[edit]
Film produces a first generation image, which contains only the information admitted through the
aperture of the camera. Trick photography is more difficult with film; in law enforcement and
where the authenticity of an image is important, like passport or visa photographs, film provides
greater security over most digital cameras, as digital files may have been modified using a
computer. However, some digital cameras can produce authenticated images. If someone
modifies an authenticated image, it can be determined with special software.
[20]
SanDisk claims to
have developed a write-once memory stick for cameras, and that the images once written cannot
be altered.
[21]


Nikon film scanner, right, which images 35 mm film for digital input.
From an artistically conservative standpoint, some practitioners believe that the use of film offers
a more authentic mode of expression than with easily enhanced digital images. As with the
earlier transition from oil painting to photography, or fromphotographic plates to film photography,
older methods are more expensive, thus encourage more selectivity and additional
consideration.
[22]

Cost[edit]

8. Film and digital imaging systems have different cost emphases. Digital cameras are significantly
more expensive to purchase than film equivalents. Prices are however dropping rapidly due to
intense competition. Film cameras, on the other hand, are quite inexpensive to purchase,
especially used equipment. But film and development costs are ongoing.
[23]
However, in the
digital realm, it could be argued that the constant state of technological change will cause a
digital user to keep upgrading and buying other equipment once their digital camera becomes
quickly obsolete.
[24]
Other costs of digital photography include specialist batteries, memory cards
and long-term data storage. The cost of digital editing software can be considerable, especially if
newer features are required. The emergence of very high quality phone cameras since the early
2010s are making lower end, small sensor digital cameras redundant, almost as quickly as they
grew in the last decade. Manufacturers are focusing attention to premium models such as
compact system cameras and large sensor compacts. Mobile phones such as the iPhone 5S,
Samsung Galaxy S5 and the Nokia Lumia 1020 are capable of images that can rival or beat
cheaper dedicated cameras. Inkjet printers can make low-quality prints cheaply and easily from
digital files, but high-quality printing has high costs regardless of image source.
Film industry[edit]
There are film industry specific arguments in the film vs. digital debate.
Most digital cinema is displayed in 2K resolution, which is only a small amount more resolution
than the consumer-oriented 1080p HD format.
[25]

The decline of the use of 35mm prints directly contributed to the bankruptcy of motion picture
film manufacturer Eastman Kodak Company.
[26]

Roger Ebert publicly criticized the use of DCPs after a cancelled film festival screening of Brian
DePalma's film Passion (2012 film) at New York Film Festival caused by a lockup due to the
coding system.
[27]

High profile film directors such as Christopher Nolan,
[28]
Paul Thomas Anderson
[29]
and Quentin
Tarantino have all publicly criticized digital cinema and digital cinematography, and advocated
the use of film and film prints. Most famously, Tarantino has suggested he may retire because
(although he can still shoot on film) he cannot project on 35mm prints in most American cinemas,
because of the rapid conversion to digital.
[30]
Paul Thomas Anderson recently was able to create
the most 70mm film prints in years for his film The Master (2012 film). There also are many film
directors such as Peter Jackson, Guillermo del Toro, George Lucas, andJames Cameron who
are adamant supporters of digital cinema and the potential for higher frame rates that it brings.