Light distance from plants

[Chowder]

question, I've got 2 x 600 W, HPS, and a couple LEDs. I know my Lux meter is no good for LED, but my readings are low, like 25-35k at 20" or so, and I've got to get it to 6-8" to get in the 45-55k range, but when I do this, the plants show signs of heat/light stress, no colouring, just bent leaves. Shouldn't they handle at least that much Lux? Heat and humidity is not the issue. I'm 6 weeks into flowering. Thanks

[Chowder]

Also, side note, will buds continue to fatten if they are a bit crowded? I've taken all the fan leaves I can for now. A lot of colas, not complaining, just want to maximize yield. Once again, many thanks!

[GDTRFB95]

Whats the manufacturer recommend height for the lights? My LEDS recomended during flower 18" as the closest. Dont worry about the lux. Its the par you need to look at. Par is the light plants use lux is what light is visible to human eye. Totally different things

[tyler_ hobbyist]

Lux/lumens is how most people calculate what they need for light, but a par value is what the plant actualy needs the reason most people still use lux/lumens is because par value meters are very expensive. This is how u calculate what u need for par value.

[tyler_ hobbyist]

Find out what ur par value is for example this picture is my light/par value

[tyler_ hobbyist]

So usualy I keep my light 15-18inchs away but because I dnt have the money for a par meter I use the next closet rateing 20inchs at 2170 pars. Now u take how many seconds are in a hour 60seconds x 60mins in a hour equal 3600seconds in an hour now times that by how many hours u keep ur lights on I use 24/0 so 24hours times 3,600secons equals 86,400seconds in 24hours now. 86,400seconds times 2170par equals 187,488,000. P.s umoles and par value is the same thing just different term. There's 1,000,000/ 1million umoles in 1mole. So u take 187,488,000 divide into 1,000,000 equals 187.5moles per day. Now photo strains indicas need 30-50moles per day and photo sativas need 40-60moles per day at the minimum. Now autoflowers need 1/4 to 1/2 more moles per day. As u can see above I give all my plants an average of 187.5 MOLES PER DAY. But the only reason I can give them this much is because the added co2 I give them without the co2 the plants would get light burn.

[tyler_ hobbyist]

It took me along time to figure out that calculation weeks of reserch and I finaly had to go to an old freind of mine who's a science teacher lol

[Chowder]

Thanks everyone for the input.

[tyler_ hobbyist]

Ur very welcome I hope it helps lol for co2 I also do it the cheap way, water sugar and yeast