315w CMH Bulbs? Agro vs MasterColor T12/T9

[nomofatum]

I've always used a chlorophyll wavelength chart to pick my lighting. It would be cool if there was a weed specific one. In any case, you can quickly see the main growth targets, for perfect results we would target the top of each of the peaks.



I think each and every bump on that chart is a key wavelength to hit if you want perfection.

 

[ttystikk]

But hortilux says cri means nothing to a plant.

Based on recent experience, I'm inclined to agree.

 

[ttystikk]

I've always used a chlorophyll wavelength chart to pick my lighting. It would be cool if there was a weed specific one. In any case, you can quickly see the main growth targets, for perfect results we would target the top of each of the peaks.

View attachment 3324478

I think each and every bump on that chart is a key wavelength to hit if you want perfection.

This chart does a great job of explaining why the guys running T5 in 2700k and 6500k are killing it. HPS does okay with the red post if that but little for the blue side. I was wondering if the CDM 860W lamps are a good match, considering they do a good job in the 6000k spectrum range.

 

[nomofatum]

You should also note that the left side doesn't bottom out, the graph could be extended to show usable deep blue/UVA light. So add UVB (emits UVA too) and you found the trifecta.

 

[nomofatum]

This chart does a great job of explaining why the guys running T5 in 2700k and 6500k are killing it. HPS does okay with the red post if that but little for the blue side. I was wondering if the CDM 860W lamps are a good match, considering they do a good job in the 6000k spectrum range.

Drives me nuts to see a HPS only veg, especially long ones.

 

[ttystikk]

You should also note that the left side doesn't bottom out, the graph could be extended to show usable deep blue/UVA light. So add UVB (emits UVA too) and you found the trifecta.

I was under the impression that these bulbs don't emit much if any UVA or UVB.

In addition, I've seen research that shows UVA isn't helpful; it's UVB that makes frost.

I'm not the expert, so if the above information is incorrect/out of date, do let me know!

 

[ttystikk]

Drives me nuts to see a HPS only veg, especially long ones.

You know what? Most of our veg is under 600W HPS only. Fuckin' killin' it, straight up.

 

[nomofatum]

You know what? Most of our veg is under 600W HPS only. Fuckin' killin' it, straight up.

Quality wise or quantity wise? How long of a veg?

 

[nomofatum]

I was under the impression that these bulbs don't emit much if any UVA or UVB.

In addition, I've seen research that shows UVA isn't helpful; it's UVB that makes frost.

I'm not the expert, so if the above information is incorrect/out of date, do let me know!

From what I have read UVA (315nm-400nm, starts off the left edge of that graph) is useful for general vegetative growth and especially stem growth. UVB (280-315nm) is where it drops off to not useful for growth. It's actually slightly damaging so I plan to only use it for last week of veg (to acclimate the plant) and flower(resin production time), and I will turn it off the day before I harvest. You should review the spectrum chart for the specific UVB bulbs you are looking at, I'm using a tanning bulb and it has 3.5x as much UVA as UVB.

 

[ttystikk]

Quality wise or quantity wise? How long of a veg?

We run babies and rooters under T5. After that it's all HPS for the next 6-8 weeks until they're big enough for the vertical trellis in the bloom room.

"Big enough" generally means over five feet tall by three feet wide.

 

[nomofatum]

We run babies and rooters under T5. After that it's all HPS for the next 6-8 weeks until they're big enough for the vertical trellis in the bloom room.

"Big enough" generally means over five feet tall by three feet wide.

I would love to see a before and after if you added in some 6500k to that veg room. Every HPS veg plant I see seems lanky instead of bushy. You can see the wall behind them alot. With the 6500k mostly with some 3000k, I can't see the stem let alone the wall.

 

[a senile fungus]

I've always used a chlorophyll wavelength chart to pick my lighting. It would be cool if there was a weed specific one. In any case, you can quickly see the main growth targets, for perfect results we would target the top of each of the peaks.

View attachment 3324478

I think each and every bump on that chart is a key wavelength to hit if you want perfection.

I have the 315w CMH in 4200K spectrum, here's the spectrum.




Looks like maybe I need more blue, what do you guys think?


Edit: I just realized your chart doesn't label the Y axis, I can't compare them accurately...

 

[nomofatum]

I have the 315w CMH in 4200K spectrum, here's the spectrum.

View attachment 3324657


Looks like maybe I need more blue, what do you guys think?


Edit: I just realized your chart doesn't label the Y axis, I can't compare them accurately...

That big spike of green in the middle is mostly wasted that is pretty much the difference between 4200k and 3100k. I think either 4200k or 3100k could use some blues, more for the 3100k though. The 3100k has a green spike too, I wish that was red or blue instead.

Google Image search for "chlorophyll wavelength chart" and you will get a bunch of variations.
The axis is max absorbsion %.

 

[ttystikk]

I would love to see a before and after if you added in some 6500k to that veg room. Every HPS veg plant I see seems lanky instead of bushy. You can see the wall behind them alot. With the 6500k mostly with some 3000k, I can't see the stem let alone the wall.

That's basically the reasoning behind the idea of adding one 860W CDM lamp back into each silo along with two HPS thouies. The CDM goes in dead center, each HPS would move closer to top and bottom. I'd rather use something that targets the blue band better but since this is what I've already spent money on, this is the leading candidate.

My druthers would be a digital thouie driving a Horti Super Blue MH. THAT bitch makes some frost!

 

[fishdeth]

I'm not sure tbh.

I've heard that the 315w CMH is more comparable to a 600w HPS than to a 400w... If that's the case then you'd need 2 315s to replace one 1000w.

I'm also interested in spectrum mixing, let me know what you find.

I've heard it will equal or SURPASS a 600w HPS/MH setup.
I run one in my fridge grow.
AWESOME !

 

[TheChemist77]

im using the boulderlamp cdl 315 watt, 3100k.. ive seen they have different kelvin bulbs should i look into getting a higher kelvin bulb for my veg room? i just started using the cdl's so not sure how they will compare to my old 600 w hps's yet..just started a journal running 2 315's over a 4x6 f&d table u can check it out, i also have the stat sheet on the bulbs n ballast on page 1..

https://www.rollitup.org/t/chemist77-315-watt-cdl-grow.880895/