Single light vs multiple light source

[pip313]

You have parts ordered and I respect that but I honestly feel that after a few runs your going to end up with both cmh in veg and both hps in flower after you watch the same clones act different as they lean towards one bulb or the other and they will,from experience with a 400 between two 1000. The ones that grew toward the cmh didn't stretch like the ones under the 1000w.

Once we stopped talking about 3 bulbs and cmh in the center multiple bulbs stopped making sence unless the bulbs are the same type and wattage and there is a effecientcy gain.

I figured that arrangement in a single reflector solved the even distribution problem. Shoulda mentioned that a few pages ago.

 

[rives]

I think that it is going to be pretty difficult to get an even blend, but that might not be a bad thing. It would allow you to see what portion/combination actually worked the best.

I've been struggling with something along the same lines - I want to try a single 315w over my scrog, and have been debating about trying to get two over the top of it. Since the ballasts are dimmable, supposedly without impacting the spectrum or lamp life, I could then dial away to my heart's content. I've been thinking about one of the larger Bell reflectors, but trying to get the lamps set for an even distribution is a daunting task. It would be far more difficult with two different flavors.

 

[GreenThumb14]

You have parts ordered and I respect that but I honestly feel that after a few runs your going to end up with both cmh in veg and both hps in flower after you watch the same clones act different as they lean towards one bulb or the other and they will,from experience with a 400 between two 1000. The ones that grew toward the cmh didn't stretch like the ones under the 1000w.

Once we stopped talking about 3 bulbs and cmh in the center multiple bulbs stopped making sender unless the bulbs are the same type and wattage.

I guess the other option (lol) is to run the 150w cmh and 250w cmh in the same hood, one on each end. Then other side of the cab I could use a 400w digital with MH for veg and HPS for flower. Same strain, etc. so only diff would be lighting.

 

[GreenThumb14]

I think that it is going to be pretty difficult to get an even blend, but that might not be a bad thing. It would allow you to see what portion/combination actually worked the best.

I've been struggling with something along the same lines - I want to try a single 315w over my scrog, and have been debating about trying to get two over the top of it. Since the ballasts are dimmable, supposedly without impacting the spectrum or lamp life, I could then dial away to my heart's content. I've been thinking about one of the larger Bell reflectors, but trying to get the lamps set for an even distribution is a daunting task. It would be far more difficult with two different flavors.

It's really hell trying to figure this out unless you have a lot of $$ to blow in experimenting. There are so many conflicting opinions on the forums and you never know who is just talking fan-boy shit or has actual experience... Then lots of other factors come in to play like strains and cultivation methods, temperatures, etc.

 

[pip313]

Been there done that as far as trying both in same grow. It sucked. Both in same reflector properly placed would be different.

Strain makes all the difference and even master growers advice is a suggestion. Every plant acts different. Every grower acts different.

 

[Jnugg]

Do what you do how you do bro.As DHF over in vertville would say,there's many ways to skin a mule.

 

[GreenThumb14]

Do what you do how you do bro.As DHF over in vertville would say,there's many ways to skin a mule.

I just don't want to waste money and get less yield or save an extra $100 and lose out on an extra O every harvest. Like I said, I'm getting HUGE divergence in advice from the forums. Some say that 400w pure CMH kicks even a 600w HPS for yield and others say all CMH is awesome for veg and terrible for flower... Sick of this. Everyone gives their opinions and results but never mention their setup or strain.

Was thinking maybe to keep it cheap I should just set the other side of the tent up with a 400w mh/hps digital and see the diff between sides of the tent. Would like to skip the track meet and get right to the awards show, though lol.

 

[rives]

The good thing is that all of the choices work pretty damn well. Trying to fully optimize your space/wattage/etc is a different story. Whatever you do, it's going to perform well. Whatever you do, you are going to want to change it later. Have fun with it and don't stress over it.

 

[pip313]

It really is strain dependent. Max use of veg is pure cmh max use of flower is pure hps. The blue in cmh is not optimal for flower unless you want resin over weight.

Lol if picking a light takes this long your gonna be studying nutes for a month. Just kidding.

Just do a grow mixed then do it the other way and keep records to tell what was better. Lighting isn't as important as people make it seem. Hps is standard for a reason it works and its commonly available. Chm is part fad part strain dependent in flower. It's unbeatable in veg.

 

[GreenThumb14]

It really is strain dependent. Max use of veg is pure cmh max use of flower is pure hps. The blue in cmh is not optimal for flower unless you want resin over weight.

Humidity in my grow space is already very low, so resin production should be good as long as other variables are favorable for it.

Your thought is that the CMH wastes energy producing other wavelengths which aren't as favorable during flower, whereas HPS puts all of it's energy in to one nearly monochromatic wavelength that the plants utilize more during flower, so it's more "intense" and therefor yields more?

What about 3000k CMH bulbs? That's not far off from HPS, has more red.

Just one other thought/question to help eliminate possible choices...

What are your guys thoughts on using the 3x 150w 3K Philips CMH's, arranged in a single A/C hood in a Y arrangement?

It would give me 50w sq/ft with 480w of total power consumption with an initial "combined" output of 42K lumens.... The one thing that I really like about that setup is that it's all electronic ballasts and I would get really nice light coverage with even output from the reflector, so all area's of the canopy should thrive.

 

[GreenThumb14]

The good thing is that all of the choices work pretty damn well. Trying to fully optimize your space/wattage/etc is a different story. Whatever you do, it's going to perform well. Whatever you do, you are going to want to change it later. Have fun with it and don't stress over it.

I hear ya. In the Fall I am relocating to Washington, so I'll feel a lot more comfortable about growing... But right now I'm trying to get some experience and get this strain dialed in but I have to do it all on a budget and under power consumption constraints. Knowing that good yield is pretty light dependent I don't want to blow $ on an inferior setup.

 

[pip313]

My thoughts are that yellow red is for flower blue is for veg. Very old thinking but it seems right. Both can't be bad in the original 3 bulb setup you were talking about at first but only in that exact setup would I personally try to use cmh again for weight in flower. Personal smoke weight not as important and quality is then cmh.

 

[rives]

Regarding the (3) 150's, I know that you want to stay away from the mag ballasts, but I think that a single 400 would be a better choice. Trying to fit the lamps into the hood & wiring them is not a problem - getting even distribution with inevitable variations in overlap and the potential for hot spots are what would worry me.

 

[pip313]

Your best bet really is one hps in flower, atleast till you know the strain. Make it as simple as possible and spend your money on ph and EC meters. Control of nutrients is way more important than light power. I've yielded pathetic before and it wasn't because of lack of light.

 

[GreenThumb14]

Alright, so you think the 3x 3K bulbs in the Y arrangement in single hood would give good results? I guess if I lose a little bit of yield but get an overall better taste and smell it still works out the same.

 

[GreenThumb14]

Regarding the (3) 150's, I know that you want to stay away from the mag ballasts, but I think that a single 400 would be a better choice. Trying to fit the lamps into the hood & wiring them is not a problem - getting even distribution with inevitable variations in overlap and the potential for hot spots are what would worry me.

I could ditch the hood and instead get a flat sheet of aluminum and have the edges bent down to a 45 or 60 degree angle...

As for overlap, I think in the Y arrangement there would be good overlap between the bulbs, every spot should be lit up pretty well... At least as good as a single 400w and then some. As for hot spots... Eh, they're only 150w bulbs putting out 14K lumens initially, not worried about hot spots.

I'm just so turned on to using multiple 150s cuz of the efficiency and extra 50w.

 

[rives]

Take a look at the a/c hood test thread where the light intensity is measured on a grid below the hood. It is a real eye opener concerning the difficulty of getting even distribution, and they are all single-lamp hoods.

 

[pip313]

Building a hood in a y shape and venting it may be hard. Only you know how you want your fans arranged.

The y shape doesn't seem like it would make a even pattern in a square reflector or room.

 

[pip313]

I really would put my effort into nutrient knowledge not lights. Lights come second and get no thought once in place.

 

[GreenThumb14]

Take a look at the a/c hood test thread where the light intensity is measured on a grid below the hood. It is a real eye opener concerning the difficulty of getting even distribution, and they are all single-lamp hoods.

Just took a look at it... Not too surprised to see where the light drops off the most, which is why I think using multiple bulbs in the hood would help distribution quite a bit.

Honestly, if I wasn't under power constraints I would just use 2 600w HPS and be done with this lol