I was looking for some advice on how to change from cheap Amazon lights which put out 125 par to a spider farmer 4000 which I can get over 1300 Par I’m running in a 4x4 tent mounted close to the ceiling dimmed down to 20% giving me around 225 par would like to achieve a higher par before flipping to flower do i gradually increase power or is it ok just to turn the power to 80% right away?
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Sounds like you're trying to determine what light distance you should do while utilizing the dimmer. I answered this on another post so the below is a copy & paste: For light distance, I have to make a video on this because this question comes up often. I'll try to make it simple:
1. Look at the grow light's PAR chart (found on the grow light's listing page)
2. Understand the general PAR ranges for cannabis plants:
200-400 PPFD seedings/clones/mother plants
400-600 PPFD veg
600-900 PPFD flowering
3. Do the monkey math to figure out light distance with the dimmer. For example, if at 12" on the par chart it shows 1000 PPFD in the middle, then a good guess is that the light dimmed down 50% will be half the amount of PAR - so 500 PPFD.
Hope that makes sense. You should then be able to make an educated guess on grow light distance using the dimmer.
This video might help you understand PAR a bit more:
I am not sure exactly what you are asking but, the amount of Photosynthetically Active Radiation (PAR) hitting your plant is a function of the light (intensity and spectral content) you are using and the distance from the light to the plant. Light intensity dissipates proportionally to the square of the distance from the light source i.e. light will be 4 times less intense when you are 2 times as far, or 9 times less intense when you are 3 times as far. You want to give your plant the maximum PAR that it can take based on its age. To do so, you can either get a more powerful light source or move it closer. It does not make sense to run a 450 W 4 feet above a plant when you could lower it 2 feet and run it at 110 W and achieve the same PAR, for example. That being said, moving the light too close to the plant can cause excessive heat and light burn. I am not sure if that is what you are asking but I hope it helps.