Sorry man, ppfd is not total output of a light source, even though you wish it to be.
LM is total light output measurement as you cannot test ppfd and know what total output this light makes, only how much falls on 1 spot, which is not how to measure total light output.
You say it is or it's not important is your opinion and your entitled to it, but it's not science, don't mix the two.
"theoretical gross output sphere measurements you may be referring to."
So all those companies that measure light in spheres are just fools you say... Interesting.
301H Evo on Samsung site shows 40LM for each 0.2w diode, Samsung are idiots too ?
Right...
Understand very simple thing, LM and PAR both represent total wavelengths at the growing spectrum, PAR just narrows that spectrum some more because of new conclusions but still not conclusive.
Still, LM is the only way to measure total light output of a light source.
It dont realy matter what the total light output is. You can have a bulb giving off just yellow and green light that gives off a high light output but it makes zero sense as the plants dont see light in that way. Ppfd is a mesurement of the waves of light the plant uses, it basicly a way of messuring what is usable by the plant or the light the plant sees that it uses.
Although most ppfd meters need to be adjusted to read some wave lenghths the plant uses as the ppfd meters dont messure some wavelenghths that good, such as uv and ir. Another thing wen messuring ppfd ppl dond do is you can change the angles the ppfd sensor is pointing and this will give you diffrent reading depending on were your messuring from in your grow room as the leaves can turn at diffrent angles to pick up the most light it possibly can rather than just pointing the meter straight up when it away from directly under the light.
To be honest these conversations are pointless, forums are full of them, yet not one person who still argues glass bulbs/ street lights are better than led has actualy put up the evidence of how they come to this conclussion, such as all the led lights and builds they have properly tested and recorded all the multiple ppfd readings from vs hid/cmh/nh and the multiple readings readings at multiple distances and in diffrent areas of the groing area or from each leaf on the plant at the angles each leaf is facing.
Then ive also seen some ppl saying leds dont have far red or ir, yet im not sure which adjusted ppfd meter they have used in testing to come up with this cus if you was to use a adjusted ppfd meter i know more than a few lights that have good amounts of ddep deep red/ir that are so far into the red/ir spectrum that those wavelenghths are shown as brown on the charts.
The carts and the proof are ther to show led wat for wat can give off more plant usable light than any hid/mh or cmh, yet no proof to say the other way around. What would be the point to put a product that costs more if it puts out less plant useble light at a certain wattage. Tech dont go backwards , it goes forwards. Led tech isnt just about groing cannabis, its tech going forward in all areas of lighting from glass gass type bulbs which is old old tech now.