Light height

Hey Zebec, dealing with custom lights without PAR charts can be a bit of a guessing game at first, but we can totally get you a solid baseline. Since she is only at day 14 and still pretty tiny, you want to take it easy so you don't fry her. I'd recommend hanging that 100w board about 24 inches above the canopy and dimming it down to around 25 to 30 percent intensity for now. Just watch how she reacts over the next few days. If she starts stretching too much and getting a long stem, just lower the light a few inches or bump the power up a tiny bit. If the leaves start curling up or looking stressed, just back it off a bit. Also, if you have a smartphone, definitely download the free Photone app. It isn't perfect, but it will give you a pretty decent rough estimate of your PPFD to help you dial things in without needing to buy expensive measuring gear. You will get the hang of it pretty quickly once you read what the plant is telling you. Happy Growing Growmie🌱

keep in mind you want to increase the PPFD over time - i'd put the lamp at a 20-30cm distance on a 20-30% atm of the light i guess. 100-300 ppfd will do in this stage.

Even if you have an accurate meter, still need to adjust based on local variables... what works for one garden will not necessarily work for another, but given context of growing, should be at least similar. I'd treat that similar to a quantum board, so 20-24" is probably fine. That's not a high-efficacy light based on diode size, so i'd shoot for closer 40w / sq ft when guessing proper size of coverage -- that is for 12 hour operation needs, since they are the greatest requirements. So, adjusting height realtive to best coverage end-to-end of canopy in a 2.5-3 sq ft area. that's where an app can help. You can compare relative intensity of central reading vs edges and corners... minimize the difference without sacrificing overall average. if you ever grow autoflowers, could potentially cover 150% larger area of whatever you figure out for an photoperiod context (18hours of operation needs vs 12 hours of operation).