bosgrowercommentedweek 16 years ago
@Smowkabowl, Here's a good, right to the point primer on light measurement.
https://www.growell.co.uk/advice/hints-tips/light-measurement-lumens-lux-par-and-micromoles
Here's a reasonable meter if you really want to dial in what your plants are getting.
https://www.amazon.com/Hydrofarm-LGBQM-Quantum-Micromol-Sensor/dp/B0055F59LA/ref=sr_1_1?ie=UTF8&qid=1547665551&sr=8-1&keywords=quantum+meter
And if you like to play with numbers, here's a conversion chart
http://www.egc.com/useful_info_lighting.php
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