Luminous Exposure Converter
Convert time-integrated illuminance among lux-seconds, lux-hours and footcandle time units.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Multiply the illuminance factor by the duration factor to normalize exposure to lux-seconds.
1 fc·h=3600/(0.3048²) lx·s; 1 lx·h=3600 lx·s
Worked example
1 footcandle-hour is approximately 38750.0775 lux-seconds. One lux-hour is 3600 lux-seconds.
Assumptions and input details
Luminous exposure is the time integral of illuminance, using photopic luminous quantities. The same measured dose is expressed in new units. This does not convert to radiometric J/m², plant DLI, camera exposure value, film response or a lux reading without a stated time history.
References: BIPM: SI derived quantities and units
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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