<a href=showthread.php?s=&postid=15404981#post15404981 target=_blank>Originally posted</a> by lynxvs
If you have a decent multimeter lying around you can just buy the sensor it makes for a cheap PAR meter about $139.00. I went with the Apogee SQ-120. Just multiply the mV reading by 5 to get the PAR reading.