MH vs HPS for yield?

[Midwest Toker]

Midwest they usually do have a lower lumen rating then hps lights.Hps lights appear brighter to the human eye because they are heavy in the orange red spectrum.So a lower lumen rating may not mean efficiency loss.Most of the halides on the market today have a spectrum more like the sun.Halides generally produce more par watt for watt. so to the human eye hps appears brighter.

Everyone who reads this thread who has any doubt should try it out.

Then show us where you are getting you par ratings for your bulb and how it compares to a HPS.

 

[Asche]

Will it hurt to switch from hps back to halide two weeks into flower?

i would switch to mh maybe the last 2 weeks of flower
it will glister up your buds a bit more in the end
from what i read at least,

usually i would suggest the mh a little longer in beginning
to hold back the stretch, if thats what you are looking for

but also depending on the K value.. also haven´t found any
4000 k mh up to now, i got one from sunmaster a 600 watt mh
with around 5000 k, will try that one with some pure sativas

 

[tokersmoke]

Admittedly i took my hydro store owners word for it.I am using a ushio which says its in the 5200k range.Many manufactures do not list the par values.lumateks hps seems to have the most par.But after hours of reading even par seems to be a value that isnt very valuable in plant growth

I may be a little in over my head.I will have to do more research before i can defend what i think.Thank for not letting rumor or hearsay be fact.I will post any more relevant info.Thanks

 

[Midwest Toker]

Midwest they usually do have a lower lumen rating then hps lights.Hps lights appear brighter to the human eye because they are heavy in the orange red spectrum.So a lower lumen rating may not mean efficiency loss.Most of the halides on the market today have a spectrum more like the sun.Halides generally produce more par watt for watt. so to the human eye hps appears brighter.

Everyone who reads this thread who has any doubt should try it out.

And that is not right either Metal Halides look brighter than HPS to us. Take a 2700k cfl at 23 watts and a 6500k at 23 watts and see which one you can stare at the longest.

 

[Midwest Toker]

And also where are you getting your information that halides produce more par watts than HPS.

 

[tokersmoke]

midwest please re read the earlier posts.Orange red spectrums are definately more bright to the human eye.I could def look at a metal halide light longer.

 

[Jhhnn]

I'd love to have the means to test a variety of lamps side by side under controlled conditions, because it's the results that really matter, not abstract measurements we might create.

Plants are adapted to sunlight, have been since time immemorial. They're actually rather inefficient at converting light to plant matter, using only a fraction of the energy they receive. Lamps or any system that could deliver the double humped spectrum that plant use would probably be ideal, allowing lower wattage to be used because high brightness in less effective wavelengths wouldn't exist. OTOH, delivering more red than the plant can use at the expense of blue that the plant could use is inefficient, as is the opposite.

Older formulations of both HPS & MH were deficient at one end of the spectrum or the other, with cannabis growers preferring HPS because of more red, more of what plants use during flowering. Things have changed, however, with modern MH, CMH & dual arc lamps delivering more PAR watts across the spectrum than HPS-

http://www.sunmastergrowlamps.com/PAR_Watts.htm

At that, the numbers can be deceptive. Lamps having high PAR ratings can fail to deliver in the blue & red regions because PAR is a measure of all the light between 400 & 700 nm. Only a spectrum chart can tell the true story. On that level, Hortilux blue, CMH & dual arc lamps deliver the most balanced spectrum useful to plants. With sufficient intensity, they deliver what plants need at all phases of growth, like this for my plantmax dual arc-

CMH & some modern MH bulbs mimic natural sunlight even more closely. Yield might be slightly higher higher using HPS in flowering, dunno, but that's not the whole story, anyway. If we return to the idea that plants are adapted to natural sunlight, we realize that we don't really understand what effect different wavelengths have on the composition of the lovely complex chemistry of cannabis- the terpenes & all the lesser psychoactive molecules that make the aromas, tastes & effects of different varieties distinctive. The closer we come to natural sunlight, the closer we get to revealing the true genetic expression of the plants in that regard & probably wrt phenotypes as well.

Or not. Just my two cents' worth.

 

[the gnome]

Colas forming nicely, a bit leafy tho...strain related?

so that's it....Homie?
no follow up *discussion*

 

[acridlab]

What's going on gnome?? Quick question,, do u know if those Sylvania bulbs will fire on a digital ballast?? Hope so, Im really liken the results your getting with those sylvanias, bro..
I've been mixing ushio hps with cmh for a while now, and I've been really happy,, BUT, I think u make alot of good points, n I'm gonna give those guys a try.. I mean, at that cost, I could replace the bulbs twice a run if I wanted to, at a cheaper cost from what I'm paying now.."not that I would"..but,I'm def. a believer,, my first real run was under mh, n I did better than alot of guys rocking hps.. and it wasn't even the 4000 k..

 

[tokersmoke]

great post jh!!!

 

[the gnome]

yes acridlab, they will fire on a digi ballast
but those bulbs need to be run in a vert. position base up even tho they're univ. burn position.

xecellent find jhnnn

 

[acridlab]

good lookn out, gnome.. that sux for me,, i was really wanting to give them a shot, why do the sylvanias have to be run vert??, i guess I'm gonna look at the solis tek 4000k bulbs. dammit.. i want 20 dollar bulbs too!!!

 

[the gnome]

last year i read that *some* Mh bulbs can vary in intensity and color depnding how they are positioned,
in mid bloom last month i decided to grab some batwing avengers,
bulbs are run horz. in those hood,i
started to notice they wern't as brite + seemed bluer than the bulbs in the prarabolics,
sure nuff they had changed color, not sure if it was the color that made em look less intense or what...
so back with the para's.
I'm getting such killer results with the BT 56 sylvie I just put em back in the para's.
I'll hunt for another BT 56 Mh 4000K bulb that is stable in the horz burn position for the BWs
now i did find a $16 4000K Mh bulb that runs horz that would fit in my 6" cooltubes on another project,
check out a plusrite BT 37 4000K Mh

 

[Daveholden420]

MH or hps?

MH or hps?

In my experience it has been great yields using at least one 1k mh in my flowering rooms with the rest being hps!

 

[the gnome]

In my experience it has been great yields using at least one 1k mh in my flowering rooms with the rest being hps!

Ive heard that sooooo many times.
funny no one ever considers the "great yields" adding a Mh to hps as daveholden420 just said...

maybe has nothing to do with HPS
maybe only its the MH making it better

 

[IGROWMYOWN]

Thanks gnome im using one of the cheap slyvania 4000 1ks thank to this thread I kept my Lux 600hps in there though plants seem to be happy lets see how they yield. you weren't kidding the 4000 spec does look pretty close to actual sunshine.

 

[the gnome]

that's the 1st thing I noticed was the look of the light,
wasn't what i expected,
it looks like real sunlite and that make a great 1st impression for me going into all Mh gro's

its hard to let go of hps if that's what you've relied on since your 1st indoor rodeo,
it took me 6+months before i was convinced or lol.... brave enough to take the plunge.
I still have my 2 1000w super hps horti eyes
I like to put em in along with a Mh bulb and it gives a nice contrast for taking pics hi liting the resin depending on angles

 

[flora420]

gnome, forget those light graphers, i trust ya. i mean 20 years is god damn long time to have experience, so you should know a thing or two.

could you recommend me the best mh bulb for my 1.2 x 1.2 x 2.0 meters tent? it must have 600w, or would it be better to make it 2 x 400w? i appreticate your help dude

 

[tokersmoke]

Flora im sure two 400s would work better then `1 600.

FROSTY Gnome keep it going

 

[Midwest Toker]

midwest please re read the earlier posts.Orange red spectrums are definately more bright to the human eye.I could def look at a metal halide light longer.

Are eyes are most efficient in the green and yellow spectrum.

.And jhhhn is correct and I thank him for posting that. Also science has proven that it takes almost twice as much energy to produce a blue photon as it does to produce a red photon.