Reproduce mean PPFD, sample spatial spread and same-basis DLI from one completed canopy measurement-grid aggregate, then reconcile responsible and independent records.
A quick decision brief for this specific tool
One de-identified completed production, commissioning or reviewed-training canopy PPFD map record; responsible source/revision/date; crop/stage/time applicability; exact canopy plane, mapped boundary and grid/point-level retention; instrument/model/serial/type; calibration and spectral applicability; method/orientation/cosine response; fixture configuration; ambient/background treatment; environment/stability; resolution/uncertainty; completed photoperiod schedule/control; external target/acceptance, safety, responsible review and retention records; point count, PPFD sum, sum of squares, minimum and maximum; completed mean source/value; completed same-basis hours and DLI source/value; and an optional independent same-grid source, mean and DLI
Aggregate-consistency checks; reproduced mean PPFD, sample variance/standard deviation and zero-mean-safe CV; same-basis calculated DLI; completed mean and DLI signed, absolute and relative differences; completed-DLI-implied mean when time is positive; and optional independent mean/DLI reconciliation
Validate every provenance and bounded value; require at least two whole retained points; check sum and mean against count/extrema and sum of squares against mathematical lower and maximum-based upper bounds; divide sum by count; calculate sample spread with n−1; multiply only that completed-map mean by the completed 0–24-hour source duration and 0.0036; then compare completed and optional all-or-none independent records without clamping signed differences
Choose your path
Independently reproduce mean PPFD, sample spatial spread and same-basis DLI from one completed source-owned canopy-plane measurement-grid aggregate, then reconcile completed and optional independent records without inferring delivered light from fixture watts or efficacy.
Verify a copied mean PPFD and DLI from retained point readings without receiving a generic crop target or fixture prescription.
Preserve the exact canopy plane, grid, sensor, configuration, background-light and schedule records, then enter the completed aggregates and source-reported results.
Sees reproducible mean, sample SD/CV and DLI differences while target suitability, uniformity acceptance and corrective action remain with the responsible record.
Keep instrument, calibration, spectrum, orientation, configuration, environment, uncertainty and point-level retention attached to one revision.
Check aggregate consistency against count and extrema, review the same-time DLI basis, and add an independent record only when grid, plane, configuration and schedule all match.
Gets arithmetic and transcription QA without mistaking agreement for map completeness, sensor validity, photometric acceptance or installation approval.
Understand why fixture wattage and nominal PPE cannot establish spatially delivered canopy light.
Run the reconstructable four-point example, inspect retained grid provenance and compare mean, sample spread and DLI calculations.
Can explain the quantity/time formulas and why point data, geometry, sensor applicability, crop target and safety decisions remain external.
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
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Keep the crop/time applicability, mapped boundary, point identities, sensor, calibration, spectral/cosine response, fixture state and geometry, background light, environment, uncertainty and responsible review with the same source. Aggregates cannot reconstruct missing point data.
Input = retained point-grid aggregates from one exact canopy plane and revisionThe worksheet requires at least two retained points and checks aggregate consistency against count, minimum and maximum. CV is sample SD divided by mean when mean is positive; it is descriptive arithmetic, not a platform uniformity verdict.
Mean = sum ÷ n; sample SD = √[(sum of squares − sum²/n) ÷ (n−1)]Use only the source-owned 0–24-hour schedule applicable to that mean. Compare calculated values with the responsible and optional independent same-grid records using signed, absolute and zero-safe relative differences; agreement validates no target, map, sensor or safety decision.
DLI = completed-grid mean PPFD × completed hours × 0.0036Updated: August 2026
Four retained readings—100, 200, 400 and 500 µmol/m²/s—produce sum 1,200 and sum of squares 460,000. The worksheet reproduces mean 300, sample SD about 182.574, CV about 60.858% and 16-hour DLI 17.28 without judging adequacy.
A reviewer links point-level data to the exact sensor calibration, fixture count/output/dimming, mounting geometry, ambient-light treatment, environment and measurement sequence before checking the reported mean and DLI.
A second calculation may be entered only when it uses the identical point set, plane, fixture/background condition and time basis. Differences expose arithmetic or transcription only; another map or schedule requires another run.
Use this worksheet only after a responsible source has completed a canopy-plane PPFD measurement grid and retained every point reading. Enter the source-owned count, sum, sum of squares, extrema, mean and same-basis photoperiod/DLI records to reproduce aggregate arithmetic and expose transcription differences. Fixture wattage, rated PPF or efficacy cannot establish delivered canopy PPFD without the applicable geometry and measurement evidence.