Spectrometer and Quantum Sensor can cost hundreds to thousands of dollars and not every grower can afford them. A Lux meter app on phone can be used to ensure even light spread across canopy and give estimate of Lux. Use a calibrated Lux meter for better accuracy. Just divide the Lux value you are getting with the Lumens/PPF ratio to get the PPFD value. Use calculator at the end of this page.
This guide gives an estimate for converting Lux to PPFD. Data used in this calculations is from independent lab reports or spectrometer. The converted PPFD data will be accurate if the entered Lux data is accurate.
Version |
Lumens* |
PPF* | Lumens/PPF |
QB 288 V2 Rspec | 81138.43* | 1256.92* | 64.55337 |
QB 648 Diablo | 55825.85* | 911.36* | 61.25554 |
QB 288 V2 3000K | 80833.17* | 1178.05* | 68.61607 |
QB 288 V2 4000K | 13421* | 193* | 69.5388 |
QB 96 Elite V2 | 53840.87* | 810.44* | 66.4341 |
*Use for reference only. Every Board spectrum may be slightly different. Board temperature and Phosphorus aging also change spectrum causing Lumens/PPF to shift over time.
Seedlings, Clones | Under 100 PPFD |
Veg, Greens | 150 PPFD - 400 PPFD |
Extended Veg with healthy plants | 350 PPFD to 500 PPFD |
Flowering, Fruits | 400 PPFD to 800 PPFD |
Flowering with Supplement CO2 | 600 PPFD to 1100 PPFD |
Chart is for reference only. Plant response may vary due to plant types and environmental conditions.
Horticulture Lighting Group Canada
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