DX number: Difference between revisions
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{{about|film emulsion identifiers|Document Exchange mail, courier and logistics in the United Kingdom|DX Group}} |
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{{Unreferenced|date=December 2009}} |
{{Unreferenced|date=December 2009}} |
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[[Image:Interleaved 2 of 5 135 film barcode.png|thumb|''DX I2/5 barcode on a 135 film cartridge'']] |
[[Image:Interleaved 2 of 5 135 film barcode.png|thumb|''DX I2/5 barcode on a 135 film cartridge'']] |
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==DX barcode== |
==DX barcode== |
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For 135 film cartridges the DX number is [[hash function|hashed]] to produce a four digit code. A suffix digit for the number of exposures and a manufacturer's proprietary prefix digit are concatenated to form a 6 digit decimal code. The code is printed in [[human-readable]] text and also represented as an [[Interleaved 2 of 5]] [[barcode]]. Size and position conform to the [[American National Standards Institute|ANSI]]/NAPM IT1.14:1994 standard. |
For 135 film cartridges the DX number is [[hash function|hashed]] to produce a four digit code. A suffix digit for the number of exposures and a manufacturer's proprietary prefix digit are concatenated to form a 6 digit decimal code. The code is printed in [[human-readable]] text and also represented as an [[Interleaved 2 of 5]] [[barcode]]. Size and position conform to the [[American National Standards Institute|ANSI]]/NAPM IT1.14:1994 standard. |
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To generate digits 2 through 5, the combination code is multiplied by 16 and added to the specifier number. The result is prefixed with zeroes to make 4 digits. For the Agfa film 115-4 above, the digits would be 1844 (16 |
To generate digits 2 through 5, the combination code is multiplied by 16 and added to the specifier number. The result is prefixed with zeroes to make 4 digits. For the Agfa film 115-4 above, the digits would be 1844 (16 × 115 + 4). |
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Digit 1 is any digit from 0 to 9 and is assigned by the manufacturer. |
Digit 1 is any digit from 0 to 9 and is assigned by the manufacturer. |
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Digit 6 is a code digit for the number of full-frame exposures: 1 is for 12 exposures, 2 for 20 exposures, 3 for 24, 4 for 36, 5 for 48, 6 for 60, 0 for 72 and 7 for non-standard lengths such as 24+3. |
Digit 6 is a code digit for the number of full-frame exposures: 1 is for 12 exposures, 2 for 20 exposures, 3 for 24, 4 for 36, 5 for 48, 6 for 60, 0 for 72 and 7 for non-standard lengths such as 24+3. |
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==See also== |
==See also== |
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*[[DX encoding]] |
* [[DX encoding]] |
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{{DEFAULTSORT:Dx Number}} |
{{DEFAULTSORT:Dx Number}} |
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Revision as of 21:29, 8 July 2013
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The DX number is assigned by the International Imaging Industry Association (I3A). It uniquely identifies the type and manufacturer (sensitizer) of a film emulsion. A proprietary list of DX numbers for APS and 135 film is prepared yearly or as needed. (DX Codes for 135-Size Film, 2004, I3A). The list is available for sale from the I3A.
DX number composition
A DX number has two parts separated by a dash: the "combination code" also known as "DX Number Part 1 " followed by a "specifier number", or "DX Number Part 2". For example, Agfa Perutz 3-color 200 ISO film is assigned 115-4 (I3A).
DX barcode
For 135 film cartridges the DX number is hashed to produce a four digit code. A suffix digit for the number of exposures and a manufacturer's proprietary prefix digit are concatenated to form a 6 digit decimal code. The code is printed in human-readable text and also represented as an Interleaved 2 of 5 barcode. Size and position conform to the ANSI/NAPM IT1.14:1994 standard.
To generate digits 2 through 5, the combination code is multiplied by 16 and added to the specifier number. The result is prefixed with zeroes to make 4 digits. For the Agfa film 115-4 above, the digits would be 1844 (16 × 115 + 4).
Digit 1 is any digit from 0 to 9 and is assigned by the manufacturer.
Digit 6 is a code digit for the number of full-frame exposures: 1 is for 12 exposures, 2 for 20 exposures, 3 for 24, 4 for 36, 5 for 48, 6 for 60, 0 for 72 and 7 for non-standard lengths such as 24+3.
The barcode is located between the electrically-read silver and black DX Camera Auto-Sensing Code and the film cartridge exit lip.
The barcode is optically scanned by many film-processing machines when the cartridge is inserted for developing. (Kodak patent 5761558)