Lumens do not matter. Its all about the PAR and spectrum the bulb emits. Are you using the same light set up as the first run? Also there can be slight differences between runs. So many factors involved. Unless you have your environment dialed in and consistent. Every cycle will have its differences. And there is such a things as too much light.
neither of those measures really matter, its uMol how much usable light and PPFD how dense this light is.
Lumens mean nothing to plants but everything to humans, so if you are lighting a room for a human, Lumens might matter.
PAR measures the total spectrum, and since we are trying to mimic the sun or rather match a preferred spectrum to a preferred biology, ie a cannabis plant its good to take a note.
PAR is not relevant to humans because we cant see the entire spectrum, but it is relevant during the consumer business of buying a bulb in terms of matching the spectrum to the plants needs, after this dont worry about it, since none of this is a perfect measure of how much of that light any plant gets, so i refer you all to Micromoles or uMol and PPFD.
Micromoles and PPFD are what actually cause plants to react to the light reaching them. As PPFD increases, the light that is reaching the plant is more dense, and thus actually provides more light for the plant to use for photosynthesis, creating larger plants. As a quantifiable measurement, PPFD is a better way to determine how much light plants are receiving than lumens.
The reason you see better growth under a 1000W HID is based on PPFD alone, but dont forget, you are still wasting heaps of light and so you are spending more on electricity than you ought too.
How much light falls from the sun is not relevant either since it is not all used by plants, ie more falls than plants can use in any day cycle. About 40% is used under normal CO2 rates. EG if you want to use 100% of sunlight, you will be dead before you get there because of CO2 poisoning.
Stop wasting your money on 1000W lamps and help save the planet and your economy; learn about things properly. EG what are the limitations of plant growth and why?l How can we bend the physical and biological, what are the costs?
Next time you shop for a light or reflector, be sure to ask about the PPFD it puts out. And remember, a bright light for humans is not necessarily the right light for plants.
A plant in normal atmospheric CO2 has a limit on how many photons of light it can convert. So I would argue most of you indoor growers are wasting watts and contributing to global pollution of the wider environment because you dont understand the basic, and fundamental physical limitations of biology.
here are some basic definitions to help
- Photon: A quanta, or particle, of light
- Micromole: a way to measure the amount of a substance, or in this case the number of photons passing through a target area, one micromole of light equals just over 62 quadrillion photons
- Photosynthetically Active Radiation (PAR): all radiation with a wavelength of 400nm-700nm that is used for photosynthesis
- Photosynthetic Photon Flux Density (PPFD): a measurement of PAR; the number of photons falling on a given area in a given amount of time, typically measured in micromoles per square meter per second
Added the data on this site is very weak imo. Be careful because of that. You all have browsers since you are on a website. I therefore, urge you look outside of the cannabis forums to tighten up any data before posting. Being properly informed is the ony way to insure you arent wasting money on marketing babble
