Ok, that's actually a little low on lux bro. I am really surprised by that number. I was thinking it was going to be 40000, and then you could back off a little. Usually 25000 is minimum for ok growth in flower, 35 to 45 is good growth, and 45 to 65 for rigorous growth. Some plants have even gotten up to 90000 in my tent right next to the lights.
Not sure what to tell you now. They look like they are being burnt, but maybe they are actually not getting enough. Try getting lux around 30000 and then wait two hours and see how they react. The we I'll know. We need to get your meter dialed in to where they need to be, and this is the only way to do it. Drop light to 30000 lux and then report after two hours how they look.
I think i did not understand the swivel thing. I took my phone and made a flat circle with the phone in my hand, just in the middle of both canopys (not the middle under the light! ) without pulling the line to the highest tops.
Maybe you have an external link or post how i should measure to adapt the cob distance.
I m at 52 cm now, and this is the advice from the building company...under.