Description
Calculate a supplied retouch-mask share of examined surface area.
Conservation records distinguish measured areas, source-qualified condition labels, storage clearances and light exposure. Lux-hours measure photometric exposure, whereas material response depends on spectrum and sensitivity. A nominal inverse-square distance ratio or geometric mask share does not establish an appropriate treatment or safe display limit.
Calculate a supplied retouch-mask share of examined surface area.
When to use this tool
Use Retouch Mask Area Share when you already have retouchArea, examinedSurfaceArea and need to calculate a supplied retouch-mask share of examined surface area.
How to use the tool and how it works
- Enter retouchArea, examinedSurfaceArea. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read retouchFraction, unmaskedArea. Use the output convention below.
Require examinedSurfaceArea>0 and retouchArea within [0,examined]; return retouch/examined and examined-retouch.1
| Input field | Meaning and units | Accepted input |
|---|---|---|
| retouchArea | Retouch Area | Required. Finite number; minimum 0. |
| examinedSurfaceArea | Examined Surface Area | Required. Finite number; strictly above 0. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| retouchFraction | Retouch Fraction | Required. Finite number. |
| unmaskedArea | Unmasked Area | Required. Finite number. |
{
"input": {
"retouchArea": 12,
"examinedSurfaceArea": 80
},
"output": {
"retouchFraction": 0.15,
"unmaskedArea": 68
}
}Limitations and assumptions
- Areas need the same units and measurement scope. No retouch is detected or suitability, condition or conservation treatment evaluated.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Use calibrated observations and the complete conservation, lighting or transport assessment. Check material response, geometry, history and actual condition before applying local ratios, exposure terms or labels to an object.
References
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