Data model¶

The Z Mount Product Database maintains the lens and related optical product dataset separately from the mount adapter dataset. Within each dataset, data moves through three stages from candidate research to public distribution: research results, canonical records, and distribution data. On this page, "dataset" means a collection grouped by product scope. "Research result," "canonical record," and "distribution data" identify the stages from candidate research to distribution.

Overview¶

Datasets by product scope¶

The two datasets differ in scope and in the structure used for product-specific information. Distribution data is also generated separately for each dataset.

Composite product key¶

Use the combination of a dataset namespace and id to identify a product uniquely.

Lens Full and Lens Light represent the same product collection, so they share the lenses namespace and product IDs. An id is unique within its namespace. The same id may be used in different namespaces. When you combine multiple datasets, use the composite key instead of a bare id as the primary key.

The namespace is not an additional field in the JSON. Determine it from the distribution file that contains the record. An id is a human-readable slug formed from the brand or product name, using lowercase letters and digits separated by hyphens. The relationship between words in the slug and product information is not part of the public data contract. Do not parse the brand, product name, specifications, or product type from id; use the corresponding fields instead.

The canonical record examples show id, identity, lifecycle, and officialProductPages as common basic fields. Product-specific information uses different structures, and separate JSON Schemas validate research results and canonical records for each dataset.

From research result to distribution data¶

Both datasets have one research result for each candidate product. A research result records the inclusion decision and the sources used as evidence. Create a canonical record for a product with an included decision, then generate distribution data for that dataset automatically from its canonical records.

flowchart LR
  R["Research result<br>one per candidate product"] -->|Included| C["Canonical record<br>one per included product"]
  C -->|Generated automatically| D["Distribution data<br>one per dataset"]

The following example shows how the research result, canonical record, and distribution entry for the NIKKOR Z 24-70mm f/2.8 S II relate to one another. Each JSON example contains only the fields and array entries needed for the explanation and is not a complete file. The distribution example is fixed to data version 2026.09.05. The current file under dist/ may contain different values because it is updated over time.

{
  "id": "nikkor-z-24-to-70mm-f2p8-s-ii",
  "decision": {
    "status": "included",
    "recordId": "nikkor-z-24-to-70mm-f2p8-s-ii"
  }
}

{
  "$schema": "../../../../schemas/lenses/product-record.schema.json",
  "id": "nikkor-z-24-to-70mm-f2p8-s-ii",
  "productType": "lens",
  "identity": {
    "manufacturerId": "nikon",
    "brandId": "nikkor",
    "productName": "NIKKOR Z 24-70mm f/2.8 S II"
  },
  "lifecycle": {
    "announcementDate": "2025-08-22"
  },
  "officialProductPages": [
    {
      "url": "https://nij.nikon.com/products/lineup/nikkor/zmount/nikkor_z_24-70mm_f28_s_2/"
    }
  ],
  "mount": {
    "systemId": "nikon-z"
  },
  "lens": {
    "focalLength": {
      "kind": "zoom",
      "rangeMm": {
        "minimum": 24,
        "maximum": 70
      }
    },
    "opticalConstruction": {
      "groups": 10,
      "elements": 14
    }
  }
}

{
  "dataVersion": "2026.09.05",
  "datasetVariant": "full",
  "recordCount": 603,
  "referenceData": {
    "manufacturers": {
      "nikon": { "name": "Nikon" }
    },
    "brands": {
      "nikkor": { "name": "NIKKOR" }
    },
    "mountSystems": {
      "nikon-z": { "name": "Nikon Z" }
    }
  },
  "products": [
    {
      "id": "nikkor-z-24-to-70mm-f2p8-s-ii",
      "productType": "lens",
      "identity": {
        "manufacturerId": "nikon",
        "brandId": "nikkor",
        "productName": "NIKKOR Z 24-70mm f/2.8 S II"
      },
      "physical": {
        "weightMeasurements": [
          {
            "grams": 675
          }
        ]
      },
      "controls": [
        {
          "type": "focus-ring",
          "quantity": 1
        }
      ],
      "accessories": {
        "lensHoods": [
          {
            "relationship": "supplied",
            "modelNumberOptions": [
              "HB-117"
            ],
            "quantity": 1
          }
        ]
      },
      "lens": {
        "focalLength": {
          "kind": "zoom",
          "rangeMm": {
            "minimum": 24,
            "maximum": 70
          }
        },
        "opticalConstruction": {
          "groups": 10,
          "elements": 14
        }
      }
    }
  ]
}

Within the lenses namespace in this example, decision.recordId in the research result, id in the canonical record, and id in the distribution entry all match. This matching ID makes it possible to trace the same product through all three stages.

PRODUCTS.md, the product list, is generated automatically from research results and canonical records separately from the distribution data.

Lenses and related optical products¶

productType is one of lens, teleconverter, or pinhole. Product-specific specifications are recorded in the product-type block with the same name as productType. For the NIKKOR Z 24-70mm f/2.8 S II, that block is lens.

Lens Full and Lens Light¶

Lens Light contains the same products in the same order as Lens Full and uses the same product IDs. It retains the fields needed for the existing website display, but it does not add Light-only values. Each retained value and its data type match Lens Full. The only exception is that minimumFocusDistances retains only the entries tied for the shortest focus distance, while reproductionMagnifications retains only the entries tied for the greatest reproduction ratio, as described under Value-state rules.

In the NIKKOR Z 24-70mm f/2.8 S II example above, Lens Full contains the 675 g weight, 24-70 mm focal length, optical construction, controls, and accessories. For this example, Lens Light retains the weight and focal length but omits the optical construction, controls, and accessories.

Mount adapters¶

Mount adapters also use research results to record inclusion decisions and have a canonical record for each included product. Their canonical record structure differs from the structure for lenses and related optical products and has neither productType nor a product-type block.

{
  "$schema": "../../../../schemas/adapters/adapter-record.schema.json",
  "id": "mount-adapter-ftz-ii",
  "identity": {
    "manufacturerId": "nikon",
    "brandId": "nikon",
    "productName": "Mount Adapter FTZ II"
  },
  "lifecycle": {
    "announcementDate": "2021-10-28"
  },
  "officialProductPages": [
    {
      "url": "https://nij.nikon.com/products/lineup/accessory/body/ftz_2/index.html"
    }
  ],
  "mountConfigurations": [
    {
      "lensSideMountSystemId": "nikon-f",
      "cameraSideMountSystemId": "nikon-z",
      "lensRetention": null,
      "lensRearProtrusionLimits": null
    }
  ],
  "electronics": {
    "electronicContacts": true,
    "autofocus": true,
    "metadataTransmission": {
      "present": true,
      "standards": [
        "exif"
      ]
    }
  },
  "electronicServices": null,
  "conversionOptics": {
    "present": false
  },
  "mechanisms": [],
  "physical": {
    "weightMeasurements": [
      {
        "grams": 125,
        "approximate": true,
        "conditions": {}
      }
    ]
  }
}

{
  "dataVersion": "2026.09.05",
  "datasetVariant": "full",
  "recordCount": 440,
  "referenceData": {
    "manufacturers": {
      "nikon": { "name": "Nikon" }
    },
    "brands": {
      "nikon": { "name": "Nikon" }
    },
    "mountSystems": {
      "nikon-f": { "name": "Nikon F" },
      "nikon-z": { "name": "Nikon Z" }
    }
  },
  "adapters": [
    {
      "id": "mount-adapter-ftz-ii",
      "identity": {
        "manufacturerId": "nikon",
        "brandId": "nikon",
        "productName": "Mount Adapter FTZ II"
      },
      "mountConfigurations": [
        {
          "lensSideMountSystemId": "nikon-f",
          "cameraSideMountSystemId": "nikon-z",
          "lensRetention": null,
          "lensRearProtrusionLimits": null
        }
      ]
    }
  ]
}

The id for the Mount Adapter FTZ II matches between its canonical record and its entry in Mount adapter Full. There is no Light distribution for mount adapters.

Shared registries¶

The registries map manufacturer, brand, and mount-system IDs to display names. Both datasets use the same manufacturer and brand registry and the same mount-system registry.

Manufacturer and brand registry: data/product-manufacturer-brand-registry.json

Mount-system registry: data/mount-system-registry.json

Canonical records store registered IDs in identity.manufacturerId and identity.brandId. The parent directory of a canonical record is the same brand ID as identity.brandId. Research results use the same IDs in subject.manufacturerId and subject.brandId; when the brand is not established, subject.brandId is null and the result is placed under unattributed/. Lenses and related optical products use mount-system IDs in mount.systemId and, for a supplied or dedicated adapter, mount.adapter.nativeMountSystemId. Mount adapters use mount-system IDs in mountConfigurations.

The two source registries support research, authoring, validation, and distribution generation. Before the first release, a source registry contains only entries referenced by canonical records or research results. Every research decision counts as manufacturer and brand usage; mount-system usage comes from canonical records. Their structure is validated by repository-only JSON Schemas under schemas/internal/. They are not separate distribution files. Each distributed JSON instead embeds only the referenced entries in a root referenceData object. For example, a consumer can resolve product.identity.brandId through referenceData.brands[brandId].name. Each referenceData entry is currently an object containing only name. This shape allows future display metadata to be added without replacing a string value with an object.

Manufacturer, brand, and mount-system IDs remain fixed after their first publication, even if a display name changes. Published IDs are not renamed or reused. If a published ID later becomes unreferenced, this stability rule takes precedence. When that first occurs, add a mechanism that retains and validates the published ID explicitly.

File layout¶

Each dataset has directories for its research results and canonical records. Create one research result file for each candidate product and one canonical record file for each included product.

.
├── research/results/
│   ├── lenses/<brand-directory>/<result-id>.json
│   └── adapters/<brand-directory>/<result-id>.json
├── data/
│   ├── records/
│   │   ├── lenses/<brand-id>/<product-id>.json
│   │   └── adapters/<brand-id>/<adapter-id>.json
│   ├── product-manufacturer-brand-registry.json
│   └── mount-system-registry.json
├── schemas/
│   ├── shared/
│   ├── lenses/
│   ├── adapters/
│   └── internal/
├── dist/
│   ├── z-mount-lenses.full.json
│   ├── z-mount-lenses.light.json
│   └── z-mount-adapters.full.json
└── PRODUCTS.md

Use a brand ID or unattributed for <brand-directory> in the research result path.

Related pages¶

• Research result structure and inclusion decisions
• Field reference for lenses and related optical products
• Mount adapter field reference
• JSON Schema types and constraints
• Value-state rules
• Retrieve and load distribution data