Bar style leds

some plants handle more than others... i've had a couple grow into the lights and not suffer light burn. i've had others 12" from light suffer from light burn - bleaching of top cola. i let a plant grow into it until i see initial hints of a problem, then in back off a bit. it's 100% over 12 hours at all times. not all bar style led lights are equal. spreading out the diodes does help, but some generate more light per sq inch and/or more heat etc. other variables at play, including your environment. Temp RH% and CO2 will all impact what the plant can handle on top of everything else... many relativistic factors at play. what happens for one person may not happen for you.... and, what happens this grow may not be the same in a different season -- if you have those. best to observe and react.. .take some notes, mention date and environemental factors that were common during that time period etc... will be useful ifnormation even if not precisely what you need when referenced.