Source: https://guthlabs.ai/docs/instruments/time-lapse-interval-calculator/implementation/

instrument implementation / implementation-contract

# Time-Lapse Interval Calculator implementation

A source-bound implementation contract for Time-Lapse Interval Calculator; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t4-229

**Effect**: Computation or source lookup only

## Input and validation requirements

The calculator breaks or must reject an output-fps value of zero because interval calculation divides by zero. It also has an undocumented unit ambiguity and cannot calculate the requested storage estimate because no image size or storage-per-shot input is specified.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "shootDurationSeconds": 7200,
    "finalDurationSeconds": 30,
    "fps": 30
  },
  "expected_outputs": {
    "intervalSeconds": 8,
    "totalShots": 900
  },
  "working": "totalShots = finalDuration × fps = 30 × 30 = 900 shots. interval = shootDuration ÷ totalShots = 7200 ÷ 900 = 8 seconds."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/time-lapse-interval-calculator/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/time-lapse-interval-calculator/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/time-lapse-interval-calculator/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche4/tranche4-results.json`