DX number: Difference between revisions
Adding use of I2/5 on 135 film cartridges, image and example of DX code and barcode |
Adding link to HASH FUNCTION |
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A DX number has two parts separated by a dash: the "combination code" followed by a "specifier number". For example, 93-2 is assigned by the NAPM. |
A DX number has two parts separated by a dash: the "combination code" followed by a "specifier number". For example, 93-2 is assigned by the NAPM. |
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On 135 film (35 mm) cartridges the DX number is [hashed] with the number of exposures and the manufacturer's proprietary codes in a 6 digit decimal code. The code is printed in human-readable text and also represented as an [[Interleaved 2 of 5]] [[barcode]]. Most cartridges 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 code. Digit 1 is any digit from 0 to 9 and is assigned by the manufacturer. Digit 6 is a code for the number of full-frame exposures. |
On 135 film (35 mm) cartridges the DX number is [[hash function|hashed]] with the number of exposures and the manufacturer's proprietary codes in a 6 digit decimal code. The code is printed in human-readable text and also represented as an [[Interleaved 2 of 5]] [[barcode]]. Most cartridges 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 code. Digit 1 is any digit from 0 to 9 and is assigned by the manufacturer. Digit 6 is a code for the number of full-frame exposures. |
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The barcode is located between the electrically read silver and black [[DX Camera Auto-Sensing Code]] and the film can exit lip. |
The barcode is located between the electrically read silver and black [[DX Camera Auto-Sensing Code]] and the film can exit lip. |
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Revision as of 16:55, 18 May 2007
The DX number is a number, assigned by the International Imaging Industry Association, that uniquely identifies the type and manufacturer of a film emulsion. A list of assigned DX numbers for APS and 135 film is issued annually.
A DX number has two parts separated by a dash: the "combination code" followed by a "specifier number". For example, 93-2 is assigned by the NAPM.
On 135 film (35 mm) cartridges the DX number is hashed with the number of exposures and the manufacturer's proprietary codes in a 6 digit decimal code. The code is printed in human-readable text and also represented as an Interleaved 2 of 5 barcode. Most cartridges 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 code. Digit 1 is any digit from 0 to 9 and is assigned by the manufacturer. Digit 6 is a code for the number of full-frame exposures.
The barcode is located between the electrically read silver and black DX Camera Auto-Sensing Code and the film can exit lip.
The barcode is optically scanned by many film-processing machines when the cartridge is inserted for developing. (see Kodak patent 5761558)