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Ceramic Metal Halide (CMH)

simba

Sleeping Dragon
hey FB great links..
ya we want the "dimpled style" direcly over bulb and on the sides of reflector the Smooth aluminum...not all dimpled ally
 

FreezerBoy

Was blind but now IC Puckbunny in Training
Veteran
Ya' mean like this?


I've been thinking about converting an old C13 and space is at a premium. A DIY Bake-a-Round cool tube would fit nicely but, I've been wondering what to do reflector wise ... :bashhead:
 

simba

Sleeping Dragon
exactly like that.. the dimpled heps spread it a bit while the sides Reflect down... since you cant 100% aim the bends..
in a perfect world a horizontal reflector would have only thin strips of the dimpled at key points that bends cant effecianlty aim.. and the rest would be sections of Specular Distrobution Aimed exactly where it should.. (kinda look like a strobe reflector)
 

FreezerBoy

Was blind but now IC Puckbunny in Training
Veteran
Cool, thanks.



Still gotta figure out the actual shape. I notice my commercial hood has a "seagull wing" reflector. Obviously, a flat top with 45 degree sides would be easier. Or I could just use a single arc of dimpled with smooth sides attached ...

Any thoughts?
 
jdubz -- no worries.........It seems like the at the Renton Indoor store that they order in stuff for ya alot, and from talking with that guy, I sure they give price break on large quantity. I think he only had one CMH bulb there, but sure he can get more.

Freezer -- Like Simba said, nice links on the aluummy, thnx! I was hoping to just buy a reflector, enough DIY projects in building grow-tent, and looking like gonna order ballast kit, either venture or htg.............After seeing Pico's thread on the efficiency diff's in the various reflectors, though, may hafta build every damn thing for this grow, itz lookin' like :muahaha:
 
So I asked this before but did not receive a response. I have a hood with 2 fixtures. I'm running a 400 watt cmh on one end and at the other end I have a 250 cmh (Plants are vegging). Should I run both cmh's all the way through flower, or should I switch out the 250 cmh for the 270 watt super agro I also have after the stretch?
Or should I pull the 400 watt cmh and replace with a 400 watt hps and leave the 250 cmh in for flower?
Thanks
 

simba

Sleeping Dragon
as far as making those bends right above the arc tube your better off using that dimpled. ya wont get as effecient bend as you will get from the flat dimpled and then the smooth like your first drawing

what kind of hood with 2 lamps whats the size.. or model..
whats the grow size..
id keep the cmh's going..
my answer kinda depends on how far the lamps are from each other..
 
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This is a supersun shade (rectangular). I cut a hole in the other end and mounted another fixture. The 400 and 250 are tip to tip. My room is very small. 18" wide by 6 feet long. The light is on a mover. I have 2 moms in 3.5 gal pots at one end (lst), along with 20 clones in 1 gal bags (sog-2 week veg, ave height today is 8 inches).
I'm going 12/12 today. Plan was to keep both cmh until stretch is over and then replace 250 cmh with super agro, but if the concensus is to have both cmh's going the whole grow then I'm all for it. Plants are moved every other day.
 

simba

Sleeping Dragon
Green..i was concerned that they would be a few feet apart.. the more and more i think about it. id stay with the 250 and 400 cmh..
you'll still get more usable energy from the 250 cmh over the 270 hps...
 
G

Guest

I POSTED THIS IN THE GROWROOM DESIGNS FORUM BUT THOUGHT I MIGHT GET A RESPONE HERE. THANKS.

I use a 400W CMH on a magnetic HPS ballast and I love it. So i bought a 250W CMH for a Sun Systems switchalbe 250W builit-in ballast. However it will not fire. I got this from a friend and do not know about the ballast other than I have 250W HPS and MH lights that both work in it. If a 250W HPS works in the ballast, shouldnt a 250W CMH? Is there anyway I can trick the ballast into thinking the HPS is plugged in or am I having some other problem? THanks

And both bulbs are Phillups Mastercolor CMH.

n dubbya

i need to get hte yellow out of the right side (250W HPS) :bashhead:

 

simba

Sleeping Dragon
so on the left 400 cmh right 250 hps.. ya can really see the cmh staying shorter..

ya id Remove that Switch.. Thats probably the issue..
can you remove the switch (but leaving circuit intact) and try that..
 

messn'n'gommin'

ember
Veteran
First off, I apologize for my tech ignorance on how to copy the diagram for your convenience...but,

Giving a generalized appearance of a PL reflector, I'm just wondering if elongating and/or narrowing of the north-south axis of the middle section of the octagonal reflector plans on ICMag's DIY page would be a viable option. Given the relative size of the bulbs, I suppose a lengthening would not be as practical a solution as a narrowing of the mid section (say, an inch or so?). But I can see where the reflector made as laid out in the plans would certainly have merit as well. In any case, one would be well advised to leave a more or less full length "tab," of sorts, on the inside of the triangular sections for pop-riveting purposes.
Trapped heat might pose a problem in such a configuration but a series of small holes could be drilled in a circular pattern and a flange adapted to allow a vent attachment though.
 
NoWorries said:
I POSTED THIS IN THE GROWROOM DESIGNS FORUM BUT THOUGHT I MIGHT GET A RESPONE HERE. THANKS.

I use a 400W CMH on a magnetic HPS ballast and I love it. So i bought a 250W CMH for a Sun Systems switchalbe 250W builit-in ballast. However it will not fire. I got this from a friend and do not know about the ballast other than I have 250W HPS and MH lights that both work in it. If a 250W HPS works in the ballast, shouldnt a 250W CMH? Is there anyway I can trick the ballast into thinking the HPS is plugged in or am I having some other problem? THanks

And both bulbs are Phillups Mastercolor CMH.

n dubbya

i need to get hte yellow out of the right side (250W HPS) :bashhead:

I had the same problem w\my switchable ballasts. I bought a new ignitor thinking that this was the prob., but it was a 3 wire and the one in the org. ballast was a 2 wire. I sent bulb back which was brand new, they sent another and it fires right up now.
Simba-thanks for the response. I'll stay with the cmh's all the way through the grow and will post some picks of this small-ass grow.
 
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TGT

Tom 'Green' Thumb
Veteran
NoWorries, I just wanted to ask, is that picture you posted all the same strain and if so is the difference in height from the light spectrum? Just want to know becasue if so it illustrates the difference in growth from spectrum changes very well. Thanks, and nice plants!

TGT
 

przcvctm

Well-known member
Veteran
I went with Poker Toker's advice and got the Sun System I ballast. Is it best to shorten the 15' lamp cord to the minimum length necessary? Or, if cutting it down to the minimum isn't needed but 15' is too long, what is a reliable firing length?
 
G

Guest

TGT - yep, all the same strain GH SSH. They were all vegged with the 400W CMH and then when I fliiped to 12/12 I added a 250W HPS on the right side. The canopy was even (flat) when flowering started The left side stayed shorter, started flowering sooner, and are further along. Do not forget that we are comparing a 250W HPS to a 400W CMH, but they difference in the stretching is unreal. CMH all the way. I hope to get the 250W HPS into a CMH working, thanks for the ideas and keep any more suggestions coming.

Week 2 of flowering with HPS off for picture only (notice the two lights are even)


After 5 weeks of flowering (the HPS is still in there, but just way up high (along with the plants))


N dubbya
 
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Anghellic

Member
Purple Kush on the left, G13 on the right. 250 CMH in a cool tube.

hpim1394gb5.jpg
 
G

Guest

greenisgold- so you are saying it was the bulb? and the sun systems switchable built-in ballast was not to blame? If so, I'm putting my bulb in the mail tomrrow.


n dubbya
 

Uncle Remus

Member
Heres what I'm getting with a 250w'er

C99 loaded with budsites, 1 topping, no training...On left of pic


2 Dbl Strawberry Diesel's...No veg day 22


 

BonsaiBud

Member
Well, I've finished my first grow box. Before it was even done, I was starting to think how I should have done it differently. I have HPS and T5 HO flouro. I get my blues from an actinic 420 and my UVA/B and red from a pink bulb. Now disregard the fact that my first grow was Lowryder #2 under flouro. I dare say that pot plants can benefit from "green" light. Yes, that flat line in the middle of the photosynthesis curve. I dare say that I think green light encourages resin production. It is to be expected, they put on resin as a form of sunblock for all the light energy. Don't put it past me to try a box flowering under nothing but pink bulbs...just for the sake of science...and buds.

I have located a 100 watt clear CMH a bublman.com and my hydro shop has a nice, old-fashioned magnetic ballast/hood for it. Anyway, is the HPS dead? For those of us not growing on greenhouse scale (growbox people), we can add the blues and UV and even low red with reef type T5 bulbs. (Never mind the capitol investments) Add to that the dreaded stretch of HPS and my personal preference for sativas. So, do we ditch the HPS?
 
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