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Ceramic Metal Halide (CMH)

U

unthing

nice diy hood azeotrope, very excited to see your thread(or pics here)too.

i'm just wondering how would hps with supporting leds compare to cmh/cmd. for rough example 250w hps combined with 65w of blue and red leds against that 315w cmd?
 
tenthirty

tenthirty

Member
We'll know in 30 days.
On paper the agro looks to be about 30% more efficient and the spectral peaks are in the correct spots according to many research papers.

600w HPS was replaced with the 315 and I have very good history and documentation on the grow room and strain.
 
Azeotrope

Azeotrope

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tenthirty - Thanks for the feed back. Good advice on HID planet. Thanks.

You are right about the ability to adjust the recess of the bulb/socket. I have some metal stock to work with. Also plan on cutting a removable ring of hammertone (escutcheon) to finish off where the bulb enters the hood. Just having some fun with it....... Worst case scenario, I can retrofit a P.L. Lighting hood I have and go horizontal. I am a believer in vert when possible though.

NO CUTS! NO BLOOD! I expected several.

unthing - Wrong person to ask about LED...... Maybe someone else that has some experience with combining the different techs like that. Thanks for your feed back. I saw the recessed style can at a surplus store and started thinking it would be fun to play with.....

Regards to everyone.
 
U

unthing

i just thought that if this cmd really gives so much better spectre somebody could calculate it's advantages against traditional hid + some good leds (let's say whatever cree is having at the market right now). these ballasts and bulbs are harder to get at least in europe (not to mention cost) so i was pondering.
 
rives

rives

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tenthirty

tenthirty

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Good, no cuts, you have a future in sheet metal.

unthing, one advantage is no mixing of different colors of light from different locations.
The standard deviation and intensity differences are going to be considerably different between a 400w HPS and a gaggle of 5 or 10 watt diodes.
It would make it difficult to get the mix and locality problems to work well.
Reves should have some input on this, from his hybrid fixture experience.

I just don't see how you would get consistent and homogeneous light from mixing led and HPS.
 
rives

rives

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Trying to balance the relative outputs of the PL-Ls and the LEDs in the Hybrid fixture was one of my biggest concerns, and I think that this would be compounded with the increased penetration of an HID. However, OGmolton has apparently had good success supplementing HPS with some blue leds here:

https://www.icmag.com/ic/showthread.php?t=201179
 
Azeotrope

Azeotrope

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Well, after all that silliness playing with that DIY reflector. I got to measuring out and looking at the lampholder/bulb mount and I ended up around 10" tall.... Can't see getting by with that. I am at 7" on my current and know how to reduce overburden of material and get it to 5". So I think the modified P.L. Midi that has already served me well will get the duty. Really do believe that Vert is best, but hell, just the new tech bulb and all will excite me and really be a nice upgrade.

I have been so damn scattered lately! Got to playing and not thinking about height.LOL Now the thought crosses my mind that I may play with this reflector as a vertizontal.... Would make Spurr happy. If I recall he was/is a vertizontal believer.
 
rives

rives

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Here is one of the Bell Lighting Hoods that I am going to use.

picture.php

picture.php
 
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rives

rives

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Thanks. I'm not happy with the junk duct take-offs that they provided, but I'll find something better. When I finally get these into their ultimate destination, there will be three of them side-by-side and then I'll build supply & return plenums.
 
Azeotrope

Azeotrope

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So, I have a 315w 930 bulb and worked out a socket issue with the manufacturer today. Should be able to convert over as soon as the new socket arrives. However...... I keep looking at the spectral graphs of the 930 & 942 and something makes me want the 942 (4k) bulb really bad! I think it is the nice big blue spikes and the lower yellow output. Not sure that it is worth the $95 (with shipping) right now though.

Come on guys and gals - Convince me either way..... rives, tenthirty, wazzup ??????
 
rives

rives

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It looks like way more blue than optimal to me, particularly for flowering. It would be an interesting side-by-side, though.
 
Azeotrope

Azeotrope

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Solid opinion on the blue content.... I have done a little playing with adding an 8k 175w halide to the cmh, but it was hot in that cab at the time. I think blue provides a lot of energy and plants can react unpredictably (and surprisingly) to different R:B ratios.

Thanks. Still foaming at the mouth over the idea.
 
tenthirty

tenthirty

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I may be totally off base here, Stoned.

From what I've read, Extra blue will promote higher ratio of chlorophyll b to chlorophyll a.
I believe that that would be a "sun adapted" type trigger. (without the volume of the sun, less umol's.)

What it does in my led setup, is to create plants that grow more biomass.
There is also an increase in flowers overall, if you disregard the runts here and there.
Now that is for the first 30 days.
so for finishing??????
My last 30 days have gone under HPS until recently.
So, from my limited knowledge, if I had to take a guess...........
A blue shift in the last 30 days could cause the plant to keep using energy for stem and leaf growth and not for flowering.

I believe wazzup was saying kind of the same thing about the plasma light needing more red for flower pointing to hps as supplemental lighting.

As far as light to light goes, the Elite Agro is noticeably redder than the HML's, about WW spectrum of XM-L's.
 
Azeotrope

Azeotrope

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More great input. Thanks. I tend to agree with that. Where I begin to wonder is in regards to resin and general terpine response. UV is well understood and none of the CDMs are great for that, but still I think that there could be some real genetic stimulus from different spectrums and then again different spectrums applied to a different strain.

The more I think about it, as a hobby/personal medical (beat up former sports freak) who is trying to supply some good meds for my osteoarthritis and my wife's insomnia, I probably have enough $$$ tied up in this for now. LOL - Or at least that is what she would tell me! What a gem of a wife though. Stuff shows up at the front door and she just sets it out for me and says that she hopes I am enjoying myself........ Then tells me to get my ass to work and suck up the overtime. haha Not really.

930 it will be for now. 942 in the future though for fun.
 
whazzup

whazzup

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You need blue light for maintaining the photosynthetic system. Plants stay greener and healthy a lot longer with (added) blue light. Red light is more (energy) efficient usually and for plants that love red light (such as the cannabis) abundance of red light is not a problem and will drive photosynthesis effectively.

For the whole well-being of the plant a full spectrum is the best you can give it. Growers like to push a plant to the limits, which is not necessarily in contradiction with with making sure the plant stays healthy, on contrary. A green plant has much more photosynthesis than a wilted brown burned one.
 
S

setaemies

Member
Kind of loosely related to the spectrum subject, I would appreciate some thoughts:

https://www.icmag.com/ic/showthread.php?p=5534732

Azeotrope - Google grows from german sites for anecdotal experiences, those guys have been using these low wattage CMH lamps for years! Google translator is your friend if your german is rusty or non-existent. :biggrin: Hanfburg and grower.ch would be your best bets for starters. I think icmag user ThinkGreen has posted some stuff here too.
 
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