Master kush

This is a widely debated topic and basically will all come down to preference. I usually wait till about the 5th node , this will ensure that your tap root is long enough . Once you top your plant the tap roots development slows right down and take quite some time to get going again if at all . You can top before if you want but I recommend the 5th node . With happy and healthy plants they spring right back into action within a few days . I hope this information helps you on your path to becoming a master grower ! -Happy Growing!

Great some one else is using a PAR meter. The first sign of the lights being too intense is a bit of canoeing or upturned leaf blades or tips curling up ,slightly folding leaf blades signalling light stress. You may also notice some discoloration or yellowing paling of the leaves closest too the lights if she's blooming watch out for the white pistils browning prematurely. Each strain can differ in terms of how much light intensity it can handle. So since your growing photo periods running your lights 12 hrs a day in bloom you can run them at a fairly high intensity level compared to running them 18-20 hrs while in veg. You need to use a DLI ( Daily Light Intensity) calculator. https://www.waveformlighting.com/horticulture/daily-light-integral-dli-calculator This will help you calculate how much light your plants are receiving daily in Moles per day. https://www.progrowtech.com/2019/05/what-is-daily-light-integral-and-how-does-it-affect-your-crop/ From my understanding your goal is to get into the 39 moles per day range by mid bloom when buds require the highest light intensity. Then as things progress through late bloom ripening stage start decreasing the intensity. I'm currently using the same technique but i'm growing autos running my lights 20 hrs a day. My top Par reading during mid bloom will be in the 650-750 range. If I go higher I will have leaf burn for sure. Since you are running 12 hrs a day you should be able to run your a bit higher using the DLI calculator to estimate how high you need to go. I'm not going to lie so increase the Par gradually a 100-150 umoles until your comfortable with the distance. At 12 hrs a day running 1000 umoles your DLI is 43.20 so your in a good place. if you see signs of stress drop it down to 850-900 it will put you in the 39 DLI range. Hope this helps you need to do bit of experimenting there no way around it.👍

Shoot for a 5 to 20% amber the rest milky white depends on how you like your high. Always inspect buds themselves ignore the leaves. There is nothing wrong with cutting a little piece to get a better view will not hurt plant one bit.