Par meter

[giantsfan24]

I'm finally on the tail end of completing my new grow box and it occurs to me that, with a dimmable Timber LED grow light, I may need a PAR meter to make sure I'm providing the plants with the light they need in both phases of growth but I don't know if I do.

Should I spring for a PAR meter?

 

[BuddyColas]

I'm finally on the tail end of completing my new grow box and it occurs to me that, with a dimmable Timber LED grow light, I may need a PAR meter to make sure I'm providing the plants with the light they need in both phases of growth but I don't know if I do.

Should I spring for a PAR meter?

My 2 cents worth, save your money. Get a LUX meter to adjust for best height and most uniform coverage. Then use conversion factor if you want a ballpark PAR reading.

 

[giantsfan24]

It's my understanding that a lux meter measures light that humans can see not the full spectrum of light available to the plants?? Do I have that wrong?

 

[Rahz]

Or just do the calculations on paper. PPF / sq/ft * 10.7 = PPFD

If PPFD is +900, veg at about half brightness.

 

[giantsfan24]

Or just do the calculations on paper. PPF / sq/ft * 10.7 = PPFD

If PPFD is +900, veg at about half brightness.

My light is measured at 967 at full brightness, 18" above. Coincidentally, I had them measure and mark at 50% lol. Thanks @Rahz! I take if flower would be full light?

 

[BuddyColas]

It's my understanding that a lux meter measures light that humans can see not the full spectrum of light available to the plants?? Do I have that wrong?

You are right. LUX response curve peaked for human eye, BUT take LUX reading times .015 and it will get you a close PAR reading for warm cobs/strips.

 

[Rahz]

My light is measured at 967 at full brightness, 18" above. Coincidentally, I had them measure and mark at 50% lol. Thanks @Rahz! I take if flower would be full light?

Yep, 900-1000 is very good for flowering.

 

[giantsfan24]

Thank you both