light field

Position-direction definition

Record the adopted radiance definition and its authority. Levoy and Hanrahan define light fields through position and direction: [Light Field Rendering](https://www.graphics.stanford.edu/papers/light/).

1. Which definition and source govern this instance, and what quantity does the function return? definition
2. Are wavelength and time explicit coordinates, fixed conditions or integrated variables? boundary

Field versus representation

Record whether an instance denotes a physical radiance distribution, a sampled observation or an inferred representation, and how these are related.

1. Does this instance denote the optical distribution, a particular capture or a reconstruction? definition
2. Which changes in scene, illumination or time create a different field instance? boundary

Coordinate interpretation

Record reference frames, orientation, units and any reference planes needed to interpret ray coordinates.

1. How does a sample address map to a physical ray, including its direction of travel? definition
2. Which rays are excluded or singular under the chosen parameterisation? boundary

Four-dimensional reduction

Record the region supporting a four-dimensional ray representation and the assumptions permitting position along a ray to be omitted. The classic formulation uses free-space regions: [Light Field Rendering](https://graphics.stanford.edu/projects/lightfield/gamma-corrected/).

1. What evidence supports treating radiance as invariant along the represented ray segments? boundary
2. Where do occlusion, attenuation, emission, scattering or refraction invalidate the adopted transport simplification? boundary

Radiance or encoded values

Require an explicit distinction between physical radiance and relative or display-encoded channel values.

1. What units, exposure normalisation and response transformation define each value? measurement
2. Which samples are clipped, below the noise floor or affected by unresolved gain differences? measurement

Compatible ray observations

Record whether observations can be treated as samples of one field under the intended use.

1. Which spectral responses and exposure intervals contribute to each group of ray samples? measurement
2. What evidence supports combining sequential views despite possible scene motion or illumination change? provenance

Measured ray coverage

Describe the actual spatial-angular sample pattern, including finite integration footprints and missing observations.

1. What are the spatial and angular sample spacings and footprints across the supported domain? measurement
2. Which requested rays fall between measured samples or outside observed coverage? boundary

Sample lineage and error

Record geometric calibration, value provenance and validation for measured, simulated, interpolated or learned samples.

1. Which calibration records establish ray locations and directions, and with what residual error? provenance
2. Which values are inferred, and what held-out observations or other evidence bound their error? measurement

Rendering query admissibility

Record the ray support and validation required for a requested viewpoint, focus setting and synthetic aperture.

1. Do the requested viewpoint and aperture require rays outside the calibrated support? action
2. Which focus and aperture settings meet the task's stated sharpness and artifact tolerances? measurement

Disparity and depth conditions

Require geometric inference to state its calibration, correspondence and appearance assumptions and identify ambiguous regions.

1. Which calibration and correspondence assumptions support converting angular variation into disparity or metric depth? definition
2. Where do occlusion, weak texture, reflections or transparency make the inferred geometry ambiguous? boundary
3. Should the agent return an uncertainty interval, request additional views or withhold a depth estimate? action

Check these first

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these check these first hold for the sense of light field this model covers, and on what evidence? provenance

Kinds and varieties

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these kinds and varieties hold for the sense of light field this model covers, and on what evidence? provenance

Real-world use

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these real-world use hold for the sense of light field this model covers, and on what evidence? provenance

Typical measurements

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these typical measurements hold for the sense of light field this model covers, and on what evidence? provenance

Failure modes and hazards

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these failure modes and hazards hold for the sense of light field this model covers, and on what evidence? provenance

Neighbouring kinds and how to tell them apart

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of light field this model covers, and on what evidence? provenance