The DX number is a number which uniquely identifies the type and manufacturer (sensitizer) of a film emulsion. These DX numbers were assigned by the International Imaging Industry Association (I3A), which published and sold a proprietary list of DX numbers for APS and 135 film yearly or as needed. The last edition of the list, entitled DX Codes for 135-Size Film, was published in January 2009.
A DX number has two parts separated by a dash: CCC-SS
For example, Agfa Perutz 3-color ISO 200/24° film is assigned 115-4, while the equivalent Perutz 3-color ISO 100/21° film is assigned 115-3.[1]
DX Part 1 numbers, from the 2008 DX Codes document:[1]| 0 | colspan=2 | ||
|---|---|---|---|
| 1 | Agfapan, Scala | ||
| 2 | |||
| 3 | Agfachrome | ||
| 4 | Technical Pan | ||
| 5 | Agfachrome | ||
| 6 | Infrared (HS & Ektachrome) | ||
| 7 | |||
| 8 | Superia, Reala | ||
| 9 | DS-100 | ||
| 10 | Fujicolor Pro | ||
| 11 | Traffic Surveillance | ||
| 12 | Superia | ||
| 13 | |||
| 14 | |||
| 15 |
| 16 | Chrome | ||
|---|---|---|---|
| 17 | Agfacolor | ||
| 18 | Scotch Color | ||
| 19 | |||
| 20 | Ektachrome | ||
| 21 | colspan=2 (was Tudor) | ||
| 22 | colspan=2 (was Tudor) | ||
| 23 | Ektachrome, Elite Chrome | ||
| 24 | Imation Chrome | ||
| 25 | |||
| 26 | Centuria | ||
| 27 | colspan=2 | ||
| 28 | VX | ||
| 29 | colspan=2 | ||
| 30 | |||
| 31 | Perutz Primera |
| 32 | Sensia, Astia, Velvia, Provia | ||
|---|---|---|---|
| 33 | Fujifilm (APS) | ||
| 34 | Sensia, Astia, Provia | ||
| 35 | Superia | ||
| 36 | NPH, Super G, Superia, Reala | ||
| 37 | Fujifilm (APS) | ||
| 38 | Fujifilm (APS) | ||
| 39 | Superia | ||
| 40 | Impresa | ||
| 41 | colspan=2 | ||
| 42 | Fujichrome RSP | ||
| 43 | MAX / Supra 800 | ||
| 44 | Agfa-Gevaert (APS) | Agfacolor Futura | |
| 45 | Agfa-Gevaert (APS) | Perutz Primera | |
| 46 | Agfacolor, Polaroid Plus | ||
| 47 | Perutz Primera, Agfacolor |
| 48 | ||
|---|---|---|
| 49 | Agfacolor Optima | |
| 50 | Monochrome, Centuria, XG, LV, VX, JX | |
| 51 | ||
| 52 | Ektachrome | |
| 53 | Ektachrome | |
| 54 | colspan=2 | |
| 55 | colspan=2 | |
| 56 | colspan=2 | |
| 57 | colspan=2 | |
| 58 | colspan=2 | |
| 59 | colspan=2 | |
| 60 | Color Chrome | |
| 61 | colspan=2 | |
| 62 | colspan=2 | |
| 63 |
| 64 | Plus-X, Tri-X | ||
|---|---|---|---|
| 65 | colspan=2 (was 3M) | ||
| 66 | |||
| 67 | T-MAX | ||
| 68 | Era Color | ||
| 69 | colspan=2 | ||
| 70 | |||
| 71 | colspan=2 | ||
| 72 | Konica Minolta (APS) | ||
| 73 | colspan=2 | ||
| 74 | colspan=2 | ||
| 75 | colspan=2 | ||
| 76 | colspan=2 | ||
| 77 | |||
| 78 | B&W+, Gold, Proimage, Profoto | ||
| 79 | BW400CN, Kodacolor, Portra |
| 80 | |||
|---|---|---|---|
| 81 | |||
| 82 | Max, Gold, Ultima | ||
| 83 | |||
| 84 | Kodachrome | ||
| 85 | Imation Color | ||
| 86 | Ferrania (APS) | ||
| 87 | Color FG | ||
| 88 | Shenguang, Shanghai, Seagull, Rainbow | ||
| 89 | colspan=2 | ||
| 90 | B/W SHD | ||
| 91 | Eastman Kodak (APS) | ||
| 92 | |||
| 93 | Plus Digital | ||
| 94 | Eastman Kodak (APS) | ||
| 95 | Professional, High Definition, Traffic |
| 96 | MAX, Portra, Gold, Kodacolor | |
|---|---|---|
| 97 | B&W, Color Negative | |
| 98 | Pan, GA | |
| 99 | colspan=2 | |
| 100 | Color Super | |
| 101 | colspan=2 | |
| 102 | colspan=2 | |
| 103 | colspan=2 | |
| 104 | colspan=2 | |
| 105 | ||
| 106 | ||
| 107 | ||
| 108 | Universal, Delta | |
| 109 | Pan, Delta, HP5, FP4 | |
| 110 | XP1, XP2 | |
| 111 |
| 112 | Portra | |
|---|---|---|
| 113 | Agfacolor HDC / Vista | |
| 114 | colspan=2 | |
| 115 | Perutz SC / Primera | |
| 116 | Kodachrome | |
| 117 | colspan=2 | |
| 118 | colspan=2 | |
| 119 | colspan=2 (was ORWO) | |
| 120 | Color CNS | |
| 121 | Color CNS | |
| 122 | Color CNN / OCN | |
| 123 | Orwopan | |
| 124 | colspan=2 | |
| 125 | colspan=2 | |
| 126 | colspan=2 | |
| 127 |
The DX film canister barcode is printed in human-readable text and also represented as an Interleaved 2 of 5 barcode, located between the electrically read silver and black DX Camera Auto-Sensing Code and the film cartridge exit lip. The size and position conform to the ANSI/NAPM IT1.14:1994 standard. Some film-processing machines optically scan the barcode when the cartridge is inserted for developing.[2]
This film canister barcode is a six-digit number in the format PHHHHE, where:
For 135 film cartridges the DX number is hashed to produce the four-digit code HHHH. To generate this code, the combination code (aka DX Number Part 1) is multiplied by 16 and added to the specifier number (aka DX Number Part 2). The result is prefixed with zeroes, if necessary, to make four digits. For the Agfa film assigned DX number 115-4 above, the hashed 4-digit code would be 1844:
16 x 115+4=1844
The DX number can be recovered from the hashed code by dividing by 16, which gives the Part 1 number as the largest whole integer and the Part 2 number as the remainder:
| 1844 | |
| 16 |
=115+
| 4 | |
| 16 |
The suffix digit E 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.
Most film produced since 1983 contains barcodes along the bottom edge of the film, recorded in two parallel tracks. The upper track (closer to the sprocket holes) is called the "clock track" and the lower track (along the edge of the film) is called the "data track"; the data track contains the unhashed DX number.[1] [3] However, unlike the film canister DX number bar code, each frame or half-frame's data track code does not provide information about the total number of frames available in the roll.
The data track consists of:[4] [5]
This information identifies manufacturers and chemistry associated with their various film types. If the manufacturer and type of film negative is unknown, the data track can be examined to identify this information. The frame number and half-frame indicator are extensions to the original data track, added by Kodak in 1990.[4]
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | colspan=6 | |||||||||||
| 1 | 0 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 1 |
| Entry code | Film product class (79 in this example) | Film specifier (e.g., 15) | Frame no. (e.g., 23) | Half- frame | Parity | Exit code | ||||||||||||||||||||||||
For each of the three encoded numerals, the most significant digit is on the left and the least significant digit is on the right; for example, the film class is a seven-bit number encoded in positions 2 through 8; position 8 is the least significant digit, and position 2 is the most significant digit. In this example, the binary number encoded (1001111) for the film class is equal to 79 (base-10). The parity bit is set or left blank to ensure the total number of "1" bits in positions 1 through 12 plus the parity bit is even. In this example, there are nine "1" bits in positions 1 through 12, so the parity bit is set.