Hanging Height PPFD Decay Calculator
Read actual matched grow-light height/PPFD calibration within observed range; no assumed inverse-square point source, extrapolation or plant-distance recommendation.
Description
Matched lamp-height measurements can calibrate local PPFD.
Matched lamp-height measurements can calibrate local PPFD. Extended light sources need not follow a simple inverse-square model.1
Enter at least two aligned positive strictly increasing heights/nonnegative nonincreasing PPFD and positive in-range query height. Return interpolated PPFD; no extrapolation.
When to use Hanging Height PPFD Decay Calculator
Use Hanging Height PPFD Decay Calculator when you need to evaluate the supplied records under the calculation and evidence rules below. No universal distance recommendation, inverse-square assumption or plant response is supplied.
Prepare the measured crop, container, lighting or inventory records requested. Supply verified local catalogs, calibration factors and crop-stage limits; keep units and dates consistent.
How to use Hanging Height PPFD Decay Calculator and understand its results
- Prepare the measured crop, container, lighting or inventory records requested. Supply verified local catalogs, calibration factors and crop-stage limits; keep units and dates consistent.
- Enter observedLampHeightsM, matchedObservedPpfd, queryLampHeightM using the field table and calculation rules, then run the tool.
- Read interpolatedMatchedPpfd. The explanation below defines the units, signs, ordering and any flags or placeholder values.
- If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.
| Input field | Meaning | Value type; see rules below | Requirement |
|---|---|---|---|
| observedLampHeightsM | Observed lamp heights m | list of number | Required |
| matchedObservedPpfd | Matched observed ppfd | list of number | Required |
| queryLampHeightM | Query lamp height m | number | Required |
Enter at least two aligned positive strictly increasing heights/nonnegative nonincreasing PPFD and positive in-range query height. Return interpolated PPFD; no extrapolation.
PPFD=piecewise linear interpolation within measured heights Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| interpolatedMatchedPpfd | Interpolated matched ppfd | number |
{
"input": {
"observedLampHeightsM": [
0.5,
1,
1.5
],
"matchedObservedPpfd": [
400,
200,
100
],
"queryLampHeightM": 1.25
},
"output": {
"interpolatedMatchedPpfd": 150
}
}Limitations and assumptions
No universal distance recommendation, inverse-square assumption or plant response is supplied.
Numeric inputs, where present, must be finite. Follow the calculation-specific rules for overflow, underflow and exceptional cases. Numeric lists are limited to 10,000 entries; string lists to 128 strings of at most 128 characters each. The rules above may impose smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.
Alternative or Complementary methods
Use Lux to PPFD Converter: Lux describes human-vision illuminance, while PPFD describes photon flux per area. Matched spectral calibration is needed to relate them. For a complementary task, use Grow Light Footprint Coverage Calculator: A coverage grid can inventory which canopy cells receive one or several lamp footprints. Area coverage alone does not describe photon uniformity.
References
-
Hanging Height PPFD Decay Calculator — tool.io
Similar or alternative tools
- Lux to PPFD Converter
Lux describes human-vision illuminance, while PPFD describes photon flux per area. Matched spectral calibration is needed to relate them.
- Grow Light Footprint Coverage Calculator
A coverage grid can inventory which canopy cells receive one or several lamp footprints. Area coverage alone does not describe photon uniformity.