Par PPFD meters

[Hdinkleman]

Can anyone reccomend a par or pofd meter for me to buy?
do we have a sponsor on this site?

i am worried about light stress, i know i have been battling a little bit of a ph issue but im wondering if some of my effects are also from light stress as well and wondering if my light is overkill for my small area tent and i am blasting the plants too much.

i have a hlg 260 running at 100% at 24” from 90% of the canopy.
have two tall colas at 21-22”
also have a kindled micro flowering bar (24watts) pushing out IR, UV and some deep red and blue
i also run a 21 watt uvb t5 for 20-30 mins a day.

would this be enough to cause light stress or am i having a different issue altogether?

 

[Stunned]

the good ones are expensive
there's an Apogee on Amazon that's selling for 740.00

 

[Hdinkleman]

are the 100$ ones any good?

 

[Stunned]

well, from what I'v read about them on this forum, there is planty of disagreement on that subject. I'm not in a position to comment yea or nay on them because I'v never used them. But that there is so much disagreement on them surely doesn't inspire confidence
I have seen the Quantum apogee for as little as 500
On that subject there isn't much disagreement
they are excellent and measure PAR accurately

 

[Emilya Green]

I bought a cheap one off of A***** called a Uyigao UA-962. It measures FC/LUX. Since both of these measurements have to do with measuring the energy in the entire human eye visible spectrum, the values don't equate exactly with the measurements we have been used to all of these years under HID light.
We know that 25,000 lux is a good usable light in veg and in flower we seek to be at least at the 50,000 - 80,000 level under HID... but what does that equate to in terms of non-full spectrum LED light? I would think logically that 50k of focused red and blue light would be like pointing laser beams at the plants... oh wait, that is exactly what it is. Hence the confusion and the even more confusing PAR measurements.
I am going to do some experiments with my Uyigao and my new CRI 90 light and see how many LUX it says I have at various distances and wattages. I know what some others with similar lights are running theirs at, and I am going to try to equate this to the old LUX numbers and see where my lights seem to fit in. Unfortunately, CRI matters, and every brand of light, every different chip, is going to equate differently. This is where we are at right now. No one knows really where they are at.

 

[Hdinkleman]

ok, im just at the point in flowering where i am trying to ride the line of too much light and 99.99% being absorbed/used or whatever it is called.
i know last grow i was so worried about it i ran my qb at 25% at 30” and definitely did not get what i was expecting.
one of the plants is also pretty big so i dont want to squander the possibility of it putting out a decent yield of flowers.

the smaller plant is doing great, its around 25-28” under the qb with no signs of stress whatsoever.
i am having a small ph problem with the soilless medium as well so kind of not 100% sure if its even light stress, im getting a few leaves with upturned margins but its lower on the plant than the top colas so im confused

also another reason for a noob like myself to not mainline, its very confusing to wonder what part of the plant is “the bottom” because all the shoots are coming off of a horizontal main stem system

 

[Stunned]

I went started my 2nd full week of flower after a week of transition
I have 3 Quantum fixtures running at 75% capacity 25 inches from the canopy
Plants are loving it