I saw them in Nottingham in the late 90's (Real eyes realise real lies was just released) and then again a couple of months ago again in Nottingham :)
https://www.youtube.com/watch?v=DPyOhP1GTRQ
Or if humidity is high enough around the base of the plant I often see it with Fytocell which is ~ 40% air at all times I only ever see it when I run drippers 24/7
No you misunderstood what I said Lumens is useful to measure the difference in intesity between the SAME types of light they are useful to compare 250w HPS to 600w HPS but they are not useful to comparing LED's to HPS or sulphur plasma.
There is no measure for grow lighting that is accurate...
I have nothing but good things to say about UK chilli seeds so much so I decided not to sell seeds from my own crops only clones :)
I purchase my seeds from there.