How do you determine if a light is bad or not, let's hear it!

hondagrower420 said:

There are 2 spectral peaks for photosynthesis.

One for photosynthesis A and the other is photosynthesis B.

I don't know the exact nm for them.

The more light at these spectral points is what Plants care about.

Plants don't "see/use" the same light as humans.

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That's the action spectrum curve. Which a while ago we thought plants only used a little green light when in fact it's green light that drives Photosynthesis and is the wavelengths that penetrate to the lower canopy

Look up Mcree curve.

hyroot said:

That's the action spectrum curve. Which a while ago we thought plants only used a little green light when in fact it's green light that drives Photosynthesis and is the wavelengths that penetrate to the lower canopy

Look up Mcree curve.

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The green light is what penetrates the canopy of the plant.

People look past it but it is in fact the only light that penetrates through leaf.

That's for the like. I'm definitely going to read up.

Would a higher green help on the top of a plant.

Doesn't the plant "create" green light when light is filtered through the leaf?

I have anxiety and shit like this runs through my head all the time.

hondagrower420 said:

Would a higher green help on the top of a plant.

Doesn't the plant "create" green light when light is filtered through the leaf?

I have anxiety and shit like this runs through my head all the time.

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Plants reflect green light and absorb green light. The reflecting aspect is why plants are green for the most part.

You do want more green but you want an even spectrum of what the pigments absorb. There is also such thing as too much light as well. Which can stunt growth.

it's ambient temp that increases growth rate so the source is moot.

Robert Hodges said:

it's ambient temp that increases growth rate so the source is moot.

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This is incomplete at best. Increasing ambient temps only helps when all other conditions are conducive to the increased growth rate, otherwise bad things such as heat stress can happen as easily as good ones.

Robert Hodges said:

it's ambient temp that increases growth rate so the source is moot.

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There is a guys on here that does cold weather grows lol and he says temps is nothing but rh that make a plant lmao grow. . Since joining here it's a headache with all this shiznit....

But coming back to bulbs I bought a
Cheap 600hps of eBay and I have not had an issue with it, should I buy proper bulb? What difference would I notice? Just curious lol don't bite me
Lol I realised that I been answered on the page before lmao, my bad.

Robert Hodges said:

it's ambient temp that increases growth rate so the source is moot.

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Higher temps on the leaf surface can increase metabolism but so can IR light. For every increase of 10 degrees on the leaf surface almost doubles the metabolism rate of the plant. You don't need higher ambient temps to achieve this.

hyroot said:

Lux - lumens - visible light to the human eye.

Par - photosynthetically active radiation - the number of photons produced by a light source between 400 nm and 700 nm

Cri - color rendering index - the higher the cri the more even the spectral output.

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So it'd be pretty misleading to use a a luxmeter on an LED?