Ceramic Metal Halide (CMH)

[binaryfission]

Since the spectrum is so much more similar to sunlight the bud will look more "outdoor" finished under CMH to get that bald bud indoor look you could add HPS or substitute the last 30 days adding red. Or seriously cut N the last month and keep the P&K up helps cut the leaf production back quite a bit. I think a solid O/D strain would thrive vigorously CMH. I also think that land race strains would produce their full cannabinoid potential with the balanced spectrum and slightly added UV much more faithfully.
WR

This sounds like good logic. But is adding red really going to do it or is it about the ratio of light changing? ITs not like the sun says on this arbitrary date i will turn on red light.
Is anyone doing tests with cmh plus hps in late flower versus cmh plus t5ho REDs in late flower?

Great thread. I'm glad i read it all. whatissixbynine kills the whole thread around post 2100. great stuff. epic post.

 

[MEnSouRdeeZ]

This sounds like good logic. But is adding red really going to do it or is it about the ratio of light changing? ITs not like the sun says on this arbitrary date i will turn on red light.

I would have to agree with WR here, the ratio of red:blue light changes constantly, no two days are the same in a year, pls allow me to explain why i think the necessity of blue light decreases throughout flower.

Red light diffuses less than blue light--it loses less energy, so to speak, traveling in a straight line through atmosphere than blue. (The color of the sky is a product of blue light's diffusive properties) Therefore, given clear conditions, red solar radiation intensity pretty much stays constant.

So in Fall, when the sun never gets directly overhead, you have a higher ratio of red:blue than summer, because red stays the same all the time (given clear conditions).

Blue solar radiation intensity is directly proportional to how direct (not angled through the atmosphere) the solar irradiation is at any given point.

ex.- afternoon sun appears "red", because the light has traveled through more atmosphere and has diffused more of the blue light elsewhere, leaving only less diffusive red light.

When the sun is directly overhead, there is a higher ratio of blue:red light, even though the red light is similar intensity in the afternoon, the blue light is more prevalent with less atmosphere to diffuse through, and more "accumulated" diffused blue light directly "beneath" the sun.

A similar process happens starting and ending with the solstices (Shortest day and longest days of year)
total average ratio of blue:red on these days would be--shortest day=highest red: blue day of the year, longest day=highest blue:red day of the year.

Of course, when there are clouds, the ratio shifts back to blue more than red, because direct light has been blocked, and only diffuse light is available.

As you can tell blue light intensity is almost constantly changing, almost constantly shifting the ratio of red:blue

Hope that helps. This is why I use HPS in the final 1/3 or so of flower.

Also, UVB diffuses more than blue light, and follows a similar schedule. This is why I use high UVB in veg, and less and less UVB as flowering cycle progresses.

 

[whatissixbynine]

.

 

[imfrompakiman]

advancedtechlighting

advancedtechlighting

has anyone ordered from here recently? i cant seem to get a response with email for tracking number....

 

[MEnSouRdeeZ]

for fucks sakes. This is something that can be measured. Then recorded. Then averaged. There are most DEFINITELY trends... ffs...

Yes there are trends, I was trying to explain them as they're not all that complicated. I guess my post makes it more complicated than it is! . On the contrary you should see my lighting arrangement

Basically blue light intensity is dependent on the sun's angle from the horizon, where as red's intensity is more constant.

 

[whiterasta]

I suppose if one wanted to try and copy the sun it would involve using CMH and Hortilux blue and you would need to run the Hortilux during veg full time and gradually add hrs of CMH in the middle of the photoperiod until one has switched over from blue leaning to red leaning possibly even adding HPS at the last few hrs of the period. So 2-4 bulb types with spectra from the H-blue to HPS with CMH filling most of the grow/flower hrs and supplementally lit by added spectra that changes through the cycle. It could be easily done with a couple ballasts and switching devices for the output and a programable timer.
It would be interesting to do a comparison between clones grown under each individual light spectrum and the same grown under a variable multi bulb spectrum. Then do a detailed analysis of the cannabinoid profiles.
I would bet a large sum there are significant differences in expression under different lighting. Plants I have had both outside and inside may as well be different strains due to the marked difference in effect and appearance between the big light and HPS.
WR

 

[binaryfission]

@MenSOurdeez fantastic post my friend. your explanation is great and very informative. thanks. SO if one were to supplement hps flowering with blue light, could one shorten internode spacing and control stretch?

@whiterasta. i would pay to see the results of a test like that, on cannabis.

 

[jdub24]

Yes... I have recently ordered from Advancedtechlighting.com. Once in December and most recently... two days ago. Personally, they or he... does a great job! I received my first order in a matter of days and the bulbs fired up instantly. My second order, which I just placed... I gave them the wrong address by accident. As nervous as I was, I called and left emails and I received a response in a matter of hours. I pesonally have not had any issues with this company and I will be ordering from them again.
As for the bulbs... I have a ton of pictures I can post but I can tell you now, they are awesome! Its better to see for yourself and you will be blown away!

 

[whiterasta]

recent developments

recent developments

universal burn, DC, electronic, CMH ballast

Matsushita Electric Works R & D Laboratories Inc. (Woburn, MA)


This invention relates to high intensity discharge lamps and, more particularly, to a DC metal halide lamp comprising a ceramic discharge vessel. In the ceramic discharge vessel, a cathode and an anode are arranged, a discharge space is provided, metal halide and mercury fillings are contained, and a metal heat shield is especially added on the cathode side for maintaining equivalent cold spot temperature in different lamp operating positions.

Most DC metal halide lamps on the market are short arc types such as disclosed in U.S. Pat. Nos. 5,291,100 and 5,144,201 for applications such as projection, vehicle headlamp, fiber optics illuminations, etc. Until now, the majority of metal halide lamps for general lighting have been operated on AC power sources. Due to the constant demand for cost cutting of electronic ballast and the continuous effort on improving efficacy of lighting systems, low wattage DC metal halide lamps fabricated with quartz envelopes for applications in general lighting have been on the market for some time as disclosed in U.S. Pat. No. 4,281,274.

However, the existing DC quartz metal halide lamps on the market are restricted to vertical operation (±45°). When a DC quartz metal halide lamp, particularly with a formed arc tube, is operated in the horizontal position, the degree of upwards arc bulge increases significantly and creates an unfavorable local hot spot resulting in a significant CCT shift and ultimately shorter lamp life.

It is an objective of the present invention to provide a universal operating DC ceramic metal halide lamp for general lighting applications. With this invention, DC ceramic metal halide lamps utilizing a metal heat shield on cathode side are suitable for universal operation. The DC ceramic metal halide lamp also exhibits relatively better performance over its AC counterpart. Moreover, a full bridge inverter is eliminated in DC electronic ballast so that about 25% component cost reduction for electronic ballast is readily achieved.

 

[Sparky 6]

Has anyone here put together a 150 watt CMH light? Seems that most are going with the 250 and 400 watters.

If I do go ahead and put one together I'll post some shots of it.

 

[hoosierdaddy]

Most opt for the larger bulbs because you can use an HPS ballast with them. The 150's require a pulse start metal halide ballast and only a 150w metal halide bulb can be switched with the CMH. The ability to switch to HPS at any time, and the fact that the larger bulbs produce more growing power, for not much more money, makes it an easy decision.

 

[Sparky 6]

Sure the power and versatility of the bigger bulbs are great but the heat isn't. My veg space needs something smaller, and I know there are smaller veg spaces than mine out there. There's a place for the smaller CMH lamps in horticulture.

 

[knna]

Sure the power and versatility of the bigger bulbs are great but the heat isn't. My veg space needs something smaller, and I know there are smaller veg spaces than mine out there. There's a place for the smaller CMH lamps in horticulture.

Each type of lighting has its own advantages. The key is to understand them and use each one on the best application for them.

Although probably we will stop using HIDs in horticulture in the future, or at least, let them just for special situations (cold), currently they are still the best alternative to light large grow rooms.

But when you say your veg space is small and heat an issue, clearly LEDs are a better option in your case. Let HIDs for large spaces, where they are very cost effective, and when heat is not an issue.

Of course you can use small CMHs if its your preference. There is 70W models. But them arnt as cost effective as their larger counterparts. Not a problem of efficiency on this case (as happen with HPSs, which 70W models are less than half efficients than 600W ones), as CMHs, although increases their efficiency with wattage, does it on a way lower difference. But a problem of cost. An small CMH with its equipment is finally pricer than a 40W LED lamps which will do the same job. Only if the grow area is on a cold environment the small CMH may be a better choice.

 

[Sparky 6]

It may be that LEDs are better for my situation but I've already made my mind up on the CMH. Also at 150 watts efficiency is not as big a deal- it should do just fine. Really it's the quality of the light from CMH I'm after and the rest is gravy. If it were less efficient than other bulbs I would still buy it.

Most must be spooked off by the labor involved in putting together a 150 watt CMH light. That's why I'll record my project and show pics of it here as well as where I sourced my parts. Should be fun and hopefully my experience will help others.

 

[Sparky 6]

Sorry for two in a row but has anyone purchased a CMH lamp from Lighting Supply Co.?

http://www.lightingsupply.com/produ...e39&category=99172fa60656481fb998bfaa0944213c

 

[messn'n'gommin']

Not me personally, but I do appreciate the source!

Thanks!

 

[messn'n'gommin']

OK well I found some ballasts at 1000bulbs.com. Which of these are recommended?

http://www.1000bulbs.com/150-Watt-Metal-Halide-Ballast/

Without having looked at their prices, they have pdf files of Venture's ballast technical guide and a troubleshooting guide from Advance, here:
http://www.atlaslightingsupply.com/MH_HPSBallasts.html

The technical guide gives a brief, but pretty good, rundown on HID ballasts and even the differing formats within them.

Hope this isn't too late.

 

[Sparky 6]

Not me personally, but I do appreciate the source!

Thanks!

Most welcome, and that's a decent price though I don't know what they charge for shipping.

Without having looked at their prices, they have pdf files of Venture's ballast technical guide and a troubleshooting guide from Advance, here:
http://www.atlaslightingsupply.com/MH_HPSBallasts.html

The technical guide gives a brief, but pretty good, rundown on HID ballasts and even the differing formats within them.

Hope this isn't too late.

No that's great thanks. That'll be great info to include in the work log. I probably won't get to the lamp project right away since I still have a lot to do to finish my flowering and veg rooms quickly before my plants need to go to flower. And I'm moving at a pretty slow pace these days because of health. Look for it within the next month though.

BTW that's the first time I've used smilies here- there are some pretty funny ones!

 

[SrgtKilroy]

Open Rated CMH in Europe

Open Rated CMH in Europe

Found this open rated 150 W CMH in Hungary. It's from GE and has 4200K. The box said "Made in Hungary". Should have figured earlier...
Works great so far, everything is dark green and getting real dense. Can't wait to see my babies flower! Planning to switch in HPS for the last four weeks, if it works out with the heat.

Btw, has anyone tried vegging with CMH, then CMH + HPS for early flowering and finishing with pure HPS?

 

[indifferent]

I have a 400W HPS in a cooltube in a cab roughly 95cm x 45cm. The cooltube sucks for light distribution so one end of the cab has lower light levels.

i looked on ebay and spotted some incredible bargains on refurbished shop fitting lights I picked up a 70W CMH fixture with bulb for 99p with 2.95 for shipping, so I have a 70W light for under 4ukp!

I'm installing it in the next few days and will post some pics of my bargain.

What double ended 70W halide bulbs do folks recommend for flowering as I don't know how many hours use the bulb in the light will have and should probably replace it.