Telescope Field of View implementation

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

t3-017

Effect

Computation or source lookup only

Input and validation requirements

• Division by zero occurs when magnification is zero.
• Zero or negative magnification is physically invalid and should be rejected; focal lengths must be positive.
• The approximation can be inaccurate for eyepieces with significant angular distortion or when the field stop limits the view.
• Very large AFOV-to-magnification results may exceed the physically usable field of the telescope or eyepiece.

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": {
    "eyepiece_AFOV_deg": 50,
    "magnification": 100
  },
  "expected_outputs": {
    "true_FOV_deg": 0.5,
    "true_FOV_arcmin": 30
  },
  "working": "TFOV = AFOV / M = 50 / 100 = 0.5 degrees. Arcminutes = 0.5 × 60 = 30 arcminutes."
}

Other records

Sources and evidence

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

• VERIFIED_LEDGER.json
• evidence-tranche3/tranche3-results.json