No multiply this by lux or lumens per watt estimate to get umols / umol/j. Simply use the listed multiplier for your brand of chip.
Cree COB 3000K 80 CRI 0.014471
Cree COB 3500K 80 CRI 0.014240
Citizen COB 3000K 80 CRI 0.014415
Citizen COB 3000K 90 CRI 0.016079
Samsung 561C 3000K 80 CRI 0.014505
Example 3500K Cree if estimated to get 10000 lumens you would multiply 10000X.014240 and you would have a PPFD of 142 umol/m2sec
Or if for example 3500K Cree the estimate is 140 lm/ watt 140X.014240 or 1.9936 umol/j
Cree COB 3000K 80 CRI 0.014471
Cree COB 3500K 80 CRI 0.014240
Citizen COB 3000K 80 CRI 0.014415
Citizen COB 3000K 90 CRI 0.016079
Samsung 561C 3000K 80 CRI 0.014505
Example 3500K Cree if estimated to get 10000 lumens you would multiply 10000X.014240 and you would have a PPFD of 142 umol/m2sec
Or if for example 3500K Cree the estimate is 140 lm/ watt 140X.014240 or 1.9936 umol/j