ISO 5800

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Logo of the German Institute for Standardization DIN ISO 5800
Area photography
title Photography - Color negative films for still photography - Determination of ISO sensitivity
Brief description: Film speed
Latest edition 2003-11
ISO 5800

The international standard ISO 5800 was first adopted as ISO 5800: 1979 (“Photography - Determination of ISO speed of color negative films for still photography”) on February 1, 1979 and defines the light sensitivity of color negative films that are used for still photography . Film material for aerial photography and color negative films for the production of intermediate negatives are therefore outside the sphere of influence of the standard . The standard was revised on November 1, 1987 with ISO 5800: 1987 and 2001 with ISO 5800: 1987 / Cor 1: 2001 . In Germany, the standard was adopted in June 1998 as DIN ISO 5800 . Since June 2002 it has replaced DIN 4512-5 in Germany , the last edition of which dates from November 1990.

The ASA and DIN standards used before ISO 5800 for specifying film speeds have been incorporated into the ISO standard. The ISO standard specifies two values ​​for each light sensitivity, namely the linear ISO value (corresponding to the linear ASA value according to ASA PH 2.5 1960 ) and the logarithmic ISO value (which corresponds to the DIN degrees according to DIN 4512 valid from 1961 onwards and is written with degrees for better differentiation).

The following applies to both scales: the higher the number, the more light-sensitive the film. The following applies to linear ISO scaling: a double value corresponds to double the sensitivity. In the logarithmic ISO scaling, an increase of 3 ° corresponds to a doubling (as with decibels ), a difference of 20 ° corresponds to a hundred times the sensitivity.

In photography , doubling the photosensitivity of the film material means that, under given lighting conditions, the exposure time can be halved to avoid blurring , or the lens can be closed one f-stop further to achieve a greater depth of field .

Another characteristic of analog film material closely related to its sensitivity is its grain . The higher the sensitivity of the film material, the coarser the grain and the lower the resolution of the photo emulsion . Some older conventional, highly sensitive black and white films such as the Kodak Recording 2463 or the Ilford HP4 show an increased sensitivity to red (superpanchromatic sensitization ).

The most common ISO-5800 values ​​are 25/15 °, 50/18 °, 100/21 °, 200/24 ​​°, 400/27 °, 800/30 °, 1000/31 °, 1600/33 ° and 3200 / 36 °. Simple amateur cameras are often only designed for films with ISO 100/21 ° to 400/27 °. In practice, often only the linear ISO value is given, e.g. B. ISO 100 actually means ISO 100/21 °. A specification such as ISO 21 ° is also allowed in the standard.

In Japanese cameras, the previously common film speed scales in "ASA" (and / or "DIN") have been replaced by information in "ASA / ISO" since around 1982, and from around 1985 only "ISO" inscriptions can be found.

Comparison of linear and logarithmic ISO 5800 values

Sv ISO linear ISO logarithmic
(APEX) (ASA scaling 1960–1987) (DIN scaling 1961–2002)
  0.63 −1 °
−2 0.75 0 °
  1.0 1 °
  1.25 2 °
−1 1.5 3 °
  2.0 4 °
  2.5 5 °
0 3 (3.125) 6 °
  4th 7 °
  5 8 °
1 6 (6.25) 9 °
  8th 10 °
  10 11 °
2 12 (12.5) 12 °
  16 13 °
  20th 14 °
3 25th 15 °
  32 16 °
  40 17 °
4th 50 18 °
  64 19 °
  80 20 °
5 100 21 °
  125 22 °
  160 23 °
6th 200 24 °
  250 25 °
  320 26 °
7th 400 27 °
  500 28 °
  640 29 °
8th 800 30 °
  1000 31 °
  1250 32 °
9 1600 33 °
  2000 34 °
  2500 35 °
10 3200 36 °
  4000 37 °
  5000 38 °
11 6400 39 °
  8000 40 °
  10,000 41 °
12 12,500 (12,800) 42 °
  16,000 43 °
  20,000 44 °
13 25,000 (25,600) 45 °
  32,000 46 °
  40,000 47 °
14th 50,000 (51,200) 48 °
  64,000 49 °
  80,000 50 °
15th 100,000 (102,400) 51 °
  125,000 52 °
  160,000 53 °
16 200,000 (204,800) 54 °
  250,000 55 °
  320,000 56 °
17th 400,000 (409,600) 57 °
  500,000 58 °
  640,000 59 °
18th 800,000 60 °
  1,000,000 61 °
  1,250,000 62 °
19th 1,600,000 63 °
  2,000,000 64 °
  2,500,000 65 °
20th 3,200,000 66 °
  4,000,000 67 °

The values ​​4/7 ° to 3200/36 ° are defined in ISO 5800: 1987, the values ​​6/9 ° to 10,000 / 41 ° in ISO 12232: 1998, higher values ​​are "in the sense of the standard" according to the conventions presented there. extrapolated. Canon and Nikon have been using slightly different values ​​(in brackets) for some of the high sensitivity values ​​since 2009, which result directly from the multiplication. The associated Empfindlichkeitsleitwerte Sv (engl. Speed value / sensitivity ) support (also called logarithmic ASA degree known) in the calculation of the exposure settings after 2.5 1960 introduced within the ASA standard PH APEX system .

Explanations of individual sensitivities

The film sensitivity of 35mm films is legibly printed on the cartridges (red arrow) and attached as so-called " DX coding " (blue arrow) so that it can be read by the camera.

Common films for simple cameras and most applications are shown in bold .

Film speed
(ISO)
Usage
<25/15 ° Black and white document films, repro films, early color negative and slide films.
25/15 ° was produced as a fine-grain color slide film until 2004, production stopped (Kodachrome 25)

Kodak Ektar 25 was a color negative film of this speed.
Currently used only for fine-grain black and white films.

50/18 ° Nowadays little used film for very bright situations, standard sensitivity for slide films until the 1970s . Currently only available representative: Fuji Velvia 50 .

Often used in nature photography in the desert, on the sea or in snow due to the sometimes extremely high light values. Black and white films of this sensitivity are usually particularly fine-grained.

64/19 ° was only available as slide film from Kodak, the corresponding Kodachrome 64 was sharper than 50 film from other manufacturers because of the special one-layer emulsion. Production stopped in 2009.
100/21 ° since the introduction of the E-6 process at the end of the 1970s, standard sensitivity for slide film (previously mostly 50/18 °). Suitable for high quality recordings, requires in tight light conditions or z. B. Sports shots with very bright lenses, tripod or flash.
125/22 ° is used for the black and white standard film Ilford FP4 plus.

Set color negative films primarily for portraits (including Agfa Optima 125, Kodak Ektar 125).

160/23 ° is the standard for films that are intended for portraits (e.g. Kodak Portra 160, Fuji Pro 160).
200/24 ​​° Compromise between the sharper 100 and the more sensitive 400 films, because of the relatively low-light zoom lenses that have become increasingly popular since the 1980s , this is now standard for color negative film.

Color negative films of this sensitivity are mostly derived from reduced speed 400 film, slide films, however, are often derived from increased sensitivity 100 film. Also used for b / w slide film (Agfa Scala 200x).

400/27 ° Until the 1970s, highly sensitive color film or highly sensitive black and white material with limited magnification - clear grain above the postcard format. With the introduction of the APS format in the mid-1990s, however, much improved films also came onto the market for 35mm format, which today also allow much higher magnifications.
800/30 ° highly sensitive films for unfavorable lighting conditions or very short exposure times,

simple cameras often do not correctly recognize films with DX coding from ISO 800/30 ° upwards.
If the film is not recognized automatically, many cameras set ISO 100/21 ° - the pictures are unusable with slides and classic black and white film because they are completely overexposed. With color negative material, however, acceptable exposures are usually still possible despite the incorrect exposure.

≥ 1000/31 ° Specialty films that can only be used with manual exposure compensation in some cameras. You will e.g. B. used at concerts, theater performances or similar occasions where flashing is prohibited or inappropriate. Older, conventional films such as Kodak Recording have an extreme grain that severely limits the ability to enlarge, but can also be used as a stylistic device. With modern films, very thin layers are produced; the film grain can be specifically controlled for some types of film.

Sensitivity settings on digital cameras

In digital photography , the ISO value is used to indicate the adjustable exposure index. In practice, the values ​​correspond roughly to those of the film material. Since digital sensors have different transmission characteristics than silver film, the values ​​given cannot be compared 1: 1.

In contrast to film material, in digital photography it is not the grain that increases with the sensitivity, but the image noise . In addition, the range of contrast that can be displayed is reduced, which together, especially in connection with noise suppression mechanisms, has a similar quality-reducing effect on the recording.

The sensible usable sensitivity of digital sensors essentially depends on the sensor technology used ( CCD sensor , CMOS ), the effective pixel size and the internal signal processing. For compact digital cameras or smartphones with small sensors, the range of adjustable values ​​usually extends from ISO 50/18 ° to ISO 400/27 °, whereby settings of ISO 200/24 ​​° upwards can already mean a significant reduction in image quality. System cameras with larger sensors offer a much larger setting range, which often enables recordings of acceptable quality up to ISO 6400/39 °. In addition, some cameras have extended modes, depending on the model up to "ISO" 4,000,000 / 67 °, but these are subject to severe quality restrictions and are often associated with a reduction in image resolution.