Test Results: MH vs. HPS, in veg.

jawbrodt · Dec 29, 2009

I have two 400 watt systems covering 12 plants that are almost 4 weeks into veg, and they were both both using MH bulbs until 4 days ago, when I decided to do a little test. The MH bulb is only 38,000 lumens, and the HPS bulb is 55,000 lumens, so i wanted to see for myself, that the MH bulb would outperform the HPS, even with the much lower light output.

Well, after 4 days later, the plants under the MH were over an inch taller than the ones under the HPS. Holy shit, I didn't expect that much difference. :shock:

So...the clear winner is the MH, even though they put out alot less light than the HPS bulbs, of the same wattage.

I thought some people would like to hear the results of some actual testing. I am glad I tried it. :cool:

P.S. The HPS bulb was from HTG Supply, and it is supposed to have 'extra blue' added, but it didn't seem to be much help.

lemmis · Dec 29, 2009

thanx jawbrodt. always kool to hear experiment results.

sampson0420 · Dec 29, 2009

jawbrodt said:
I have two 400 watt systems covering 12 plants that are almost 4 weeks into veg, and they were both both using MH bulbs until 4 days ago, when I decided to do a little test. The MH bulb is only 38,000 lumens, and the HPS bulb is 55,000 lumens, so i wanted to see for myself, that the MH bulb would outperform the HPS, even with the much lower light output.

Well, after 4 days later, the plants under the MH were over an inch taller than the ones under the HPS. Holy shit, I didn't expect that much difference.

So...the clear winner is the MH, even though they put out alot less light than the HPS bulbs, of the same wattage.

I thought some people would like to hear the results of some actual testing. I am glad I tried it.

P.S. The HPS bulb was from HTG Supply, and it is supposed to have 'extra blue' added, but it didn't seem to be much help.

well the higher lumens could cause less stretching, so I'm not sure how definitive this test is. I've vegged under HPS with great results.

jawbrodt · Dec 29, 2009

sampson0420 said:
well the higher lumens could cause less stretching, so I'm not sure how definitive this test is. I've vegged under HPS with great results.

I had some plants the were 24" away from the HPS,(getting weak light) and i had some plants the were directly below the MH, 12" from the bulb(getting pounded), and the ones under the MH still grew alot more. I'd like to try it again someday for a longer period of time, so i could keep an eye on internode spacing, just so i could be absolutely certain. But so far, the evidence points to MH as the winner.

mygirls · Dec 29, 2009

jawbrodt said:
I have two 400 watt systems covering 12 plants that are almost 4 weeks into veg, and they were both both using MH bulbs until 4 days ago, when I decided to do a little test. The MH bulb is only 38,000 lumens, and the HPS bulb is 55,000 lumens, so i wanted to see for myself, that the MH bulb would outperform the HPS, even with the much lower light output.

Well, after 4 days later, the plants under the MH were over an inch taller than the ones under the HPS. Holy shit, I didn't expect that much difference.

So...the clear winner is the MH, even though they put out alot less light than the HPS bulbs, of the same wattage.

I thought some people would like to hear the results of some actual testing. I am glad I tried it.

P.S. The HPS bulb was from HTG Supply, and it is supposed to have 'extra blue' added, but it didn't seem to be much help.

your right plants will grow better and a bit fast under MH then HPS, that why you use MH for veg to get the best plant growth as possible and faster. your HPS is a bit dimmer then the MH but yet has more lumens. we are trying to simulate the outdoors and during the end of the summer days the sun just is not as bright as it was b4.same with the HPS dimmer but more lumens means better light penatration through the canopy. but back in the day that's all that was available for growing indoors was the MH so you can grow from start to finish with MH. its still going to give a nice yield but the buds just won't be as dense and hard compared to flowering under HPS.

Test Results: MH vs. HPS, in veg.

jawbrodt

Well-Known Member

lemmis

Well-Known Member

sampson0420

Well-Known Member

jawbrodt

Well-Known Member

mygirls

Medical Marijuana (MOD)

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