Daily Light Integral - Amount of Light Plants Receive per Day

[TerpeneTom]

"We calculate with 1000 umol m-2 s-1 for the generative phase (flowering, 12 hours cycle) and 670 umol m-2 s-1 for the vegetative phase (18 hours veg cycle). This is because your plants get 50% more light in the vegetative phase because you light them 18 hours instead of 12. The daily light integral (DLI, total amount of light the plants get per day) stays the same this way. " (Gavita)

I had not been informed of the fact that one should illuminate their plants during vegetative and flowering to achieve similar intensity (correct terminology?).

I see a lot of literature suggesting a 24/7 lighting regimen, as well as 20/4, but they don't explain why and at what point photo inhibition occurs or significant diminishing returns.

I will now employ a 8-4-8-4 vegetative schedule, per the suggestion of member d9. Thus allowing enough time during dark cycle to ensure proper utilization of stored energy. I'll need to measure the light intensity to ensure ideal illumination to ease transition to flower.

More emphasis should be place on efficient utilization of lighting, as it is a significant cost and determinant of quality. There is an ideal range and we must focus more effort to measure it seems, akin to the importance/necessity of ec/ppm tools. Is this realistic?
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[cannacultural]

Interesting idea. There was discussion on RIU (How about an 18/12 light cycle?) about using extended hours during bloom to maximise daylight hours but to still maintain 12hours dark. Curious to see some proper comparison of these alternate light cycles. The idea that light is a resource which has a process and degrees of efficiency which can be manipulated like other variables makes sense to me. The RIU thread had a lot of detractors, and fair enough. But I do like the idea of supernormal stimuli, and pushing things