led or mh and hps

K

kac123ige

Active Member
now i was thinking about getting maybe a 400w or 600w mh for vegging and a 600w hps for flowering but then i learned about LED lights and im kinda interested lolz... ive been reading alot of threads but what i think im taking from them all is that led lights can get the job done for both veg and flowering but am i correct when i say that i would have to purchase a much more expensiver led light to get decent results??

i know yeild it varies greatly based upon a lot of variables lol but, ive read a thread before on a nirvana ww that was grown with a 125w mh for veg and a 600w hps for flowering with 5 ww plants in a tent and he yielded about 285g dry combined.

now i was going to go for a light setup like this until i saw led and the advantages it has with power consumption and also its low heat generation. but what kind of led light would i be looking at if i wanted similar results? thanks for any replys :)
 
StonedBlownSkiller

StonedBlownSkiller

Well-Known Member
LEDs are way more expensive than HID and HID IMO offers better light efficiency. MH is the way to go for vegg and HPS for flower. You could get a switchable ballast to run both for less than one LED panel.
 
K

kac123ige

Active Member
yes please enlighten me more upon this ceramic metal halide haha because i just did more reading about leds and i think hps and mh is the way for me to go now but now you bring up this ??? haha
 
drice420

drice420

Member
From my personal grow experience. I grew one harvest with 6 LEDs. It was terrible. The buds were not nearly as big or dense as with a HPS. Now I am only guessing here but I would say you need at least 4x 90w leds to compare to a 600w HPS (mayb even more).

At least I'm never going back to LEDs again. But they look very sweet and it feels very cool to enter a grow room filled with leds. As you can see on my avatar (using them as veg lights when I was growing in soil).
 
G

gobbly

Well-Known Member
if you go LED, plan on spending up to 4 times what you would for a comparable HID setup. They have some advantages, but it comes at a high premium. The cheap LED's are crap and not worth it.
 
H

Harorld

Member
I am in EXCATLY the same situation, trying to figure out the ‘ol LED vs MH/HPS setup. Check out my shopping list comparison:

LED SYSTEM:

  • Secret Jardin DR100 grow tent - $189
  • LED Lumigrow ES-165- $565
  • Sunleaves WindTunnel 4" inline fan - $124.95
  • Phresh Filter 4x12 - $95
  • Clip on fan 6" x2 - $19.95 each
  • duct reducer 6" to 4" - $11
  • Duct - $20
  • Hygrometer/thermometer - $23
total: $1,068

HPS/MH SYSTEM:

  • Secret Jardin DR120 grow tent - $198.95
  • Lumatek 400W Multi Watt ballast - $155.95
  • 400w High Pressure Sodium bulb - $70
  • 400w Metal Halide bulb - $100
  • Yield Master II 6" Classic Reflector - $89.95
  • Sunleaves WindTunnel 4" inline fan x2 - $124.95 each
  • Phresh Filter 4x12 - $94 95
  • Clip on fan 6" x2 - $19.95 each
  • duct reducer 6" to 4" - $11 each
  • Duct - $20
  • Hygrometer/thermometer - $23

Around $1,064

Now I am still very much in the middle of reading up on LEDs, but anyone stating that HID lamps are more efficient etc doesn’t seem to have read the latest literature on LEDs. A cursory look on the web comes up with some interesting stuff and thinking about the lights you’re using in a much more specific way, and looking at light from the perspective of plants.

The typical rating most growers are familiar with is the “lumen.” The definition of the lumen is the total light produced within the range of the human visual response. It tells us nothing about the distribution of that light energy over the spectrum, and most importantly, it doesn’t tell us how much is useful for plants.

Plant biologists define light in the 400nm to 700nm spectral region as “photosynthetically available radiation,” or PAR. The unit for measuring PAR, micro-mols per second (μmol/s), indicates how many photons in this spectral range fall on the plant each second.

The way we’ve been talking about light systems are too broadly responsive to measure an LED’s narrow emission spectrum. They make HID light seem brighter by over-measuring yellow-green light, and make LED light seem dimmer by under-measuring red and blue light.

LEDs allow us to take a targeted approach to horticultural lighting by converting electricity into only the light energy that plants will use. Instead of wasting energy producing the broad emission spectrum of an HID lamp, the LEDs create very narrow emission spectra: 20nm to 40nm spread compared to several hundred nm for an HID lamp.

Meanwhile, LEDs are very efficient at creating light from electricity. At least 20 percent of the electrical energy put into an LED turns into light, and all this light is usable for photosynthesis. For the HPS noted above, only 10 percent of the 32 percent conversion efficiency is in the photosynthesis region, meaning that the HPS is only 3 percent efficient at creating light usable by plants.








 
G

gobbly

Well-Known Member
those LED's you listed are ones I'm not familiar with, and they don't really give diode or optics info. The spectrum is a little more restricted than I prefer, but for the money they look ok. To get something better would probably cost half again to twice as much.

Plant growers use PAR, that's what it was designed for, photosynthetic active radiation... Unfortunately most companies (especially the less expensive ones that hobbyists tend to use) do not pay attention to PAR, they go with lumens because that is traditionally what was used to rate light. If more companies released PAR ratings for their lamps you'd find that it quickly would become the standard.

Something to keep in mind though is that there are other things besides photosynthesis which light is used for. It degrades hormones, and UVB outside the par range seems to cause increased resin production. Many of these secondary features of light are not well studied. I personally think a high peak in the A/B points, but maintaining a broad spectrum, is a good way to go.
 
darkdestruction420

darkdestruction420

Well-Known Member
sorry, didnt have a chance to get back to you sooner. Philips MasterColor Ceramic Metal Halide
HPS-Retro White LampsSo maybe you have hear about the best grow light bulb on the market…or maybe not - but now you have! The Philips MasterColor Ceramic Metal Halide HPS-Retro White Lamps are something new to horticulture. These bulbs are being manufactured to replace high pressure sodium (HPS) bulbs in factories and warehouses. Along comes the indoor gardener who sees the light and gets them thinking - I bet these would grow great plants! Well they do.
Grow Light Express has been testing these lamps for years and has sold lots of them. We honestly believe in these lamps. We get asked all the time if this is such a great bulb why isn't Phillips directly selling / advertising them to the horticultural markets. Well the technical reason is that with this type of bulb they would have to retool their manufacturing plants at great costs. With the coming advanced in lighting technology (and there is really some amazing stuff heading our way) we believe that they are unwilling to spend the money until the market proves worth investing further in Ceramic Metal Halide technology.
The basics:
These bulbs can be used in BOTH vegetative and bloom cycles - no more changing lamps during your grow. NO DIGITAL BALLASTS - you will destroy the bulb. ONLY use a standard coil and core HPS ballast (dont let the name confuse you). CMH bulbs cannot handle the frequencies of digital ballasts. Of course there are exceptions to this rule as there is at least one digital ballast that is designed to work with CMH lamps. They are fairly expensive and unless you know you have one of these you don't so don't try. The Ceramic Metal Halide bulbs are positional. This means that they are designed to be EITHER horizontal or vertical (they cannot be used universally) but not both. Placing the bulb in the wrong position will cause it to fail early. A tip to success is that most gardeners are reporting better success with the use of supplemental silica. Since these bulbs will make your plants grow fast, silica is helpful. Silica is involved in cell division and overall plant strength.
Benefits:
There are many benefits to these lamps. The main reason for even considering these lamps is the fantastic spectrum of light they produce. Check out the chart below to compare to output of a CMH to a HPS lamp.

As you can see there is a great deal of light energy available in the blue spectrum as well as the red. HPS lamps produce lots of light but its not the "right" light. It is true that plants can adapt and grow well under HPS but they will do better under CMH. Think of it this way, the sun, the light we are trying to reproduce inside, is full spectrum not just a lot of yellow / red. So why just give them yellow / orange? Basically HPS has become the standard for growing in supplied lighting conditions. This is mostly historical (now) because that was the best we had…now we have alternatives.
Other benefits include they "throw" less heat, they have very little color shift (less than 200K over their life time), your plants will have less stretch (tighter internodes).
Ceramic Metal Halide FAQ:
1. I have noticed that the Ceramic Metal Halide HPS Retro bulbs produce less lumens compared to other HPS bulbs?
A: Lumens is an antiquated way of comparing grow lamps. Lumens are a scientific definition based on the human eye and NOT on a plants response curve. This is the hardest part for people considering trying the CMH's to get past. We have been snowed over by the manufacturers just focusing on the max lumens.

2. When are bigger wattage bulbs going to be available?
A: Hum…sometime soon if Phillips keeps their promise! Also there is some new Ceramic Metal Halide technology on the horizon. This may keep bigger wattages of the market but the good news is that the new ones maybe extremely more efficient so you may not need bigger wattages. We will keep you posted on this!!

3. Will they run on my DIGITAL ballast?
A: NO (unless you have a specifically designed digital ballast for CMH lamps). They must be used in HPS ballast.
 
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