Atchung! Werner.
I have a bunch of different panels all have slightly different spectrums. some are 9 years old and still functioning well.
four Blacktsars one vipar reflector and two Chinese panels. one thing they all have. is a diode or two that produce some harsh UV, in the 370 to 380 nm.
each tent runs about 475 true watts. two of the blackstars were bought at auction on ebay. the same for the Chinese panels. all the panels purchased at auction were in the 40 dollar range.
don't be fooled by the high priced panels. yes they are better than a 40 dollar china panel. BUT only a small percentage better.
a good analogy is the difference is like the difference between a Subaru and an BMW they both get you where you want to be. I have tasted many different crops from growers that have
expensive lights, and what I grow. is as good or better with my cheap lights these cheap lights can produce 5 ft. autos. and of coarse, anyone you talk to that has $600 DOLLAR panels will tell you they are the best. I get a kick out of panel manufacturers that put veg/bloom switch's on there panels. the sun does not change from veg to bloom
the sun does not stop harsh UV from hitting the plant. the UV makes the plant ooze resin to protect itself. this is what makes the cannabis POTENT.