D
Drek
Are you referring to the 315's? My 400 CMH is a fair bit cooler than my 430 Son Agro HPS...like 10 degree's cooler. A noticeable difference.
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Drek
Sry...can't edit yet. 
I just realized you're talking about the 830.
I just realized you're talking about the 830.I'm not much of a believer in some of the claims around CMH or LED's that come from vendors. Lots of hoopla. OTOH, I've had really solid results from a plantmax dual arc, and the results shown here are obviously excellent, particularly wrt internode length. I only have 6' of height, so that matters more to me than maybe other people.
I get excellent penetration from the dual arc with my just let 'em grow style- even the lowest branches have decent buds & the popcorn isn't larfy. I figure that the CMH may be even better.
I get excellent penetration from the dual arc with my just let 'em grow style- even the lowest branches have decent buds & the popcorn isn't larfy. I figure that the CMH may be even better.
I understand and concur, but from what I've been able to gather from numerous conversations with the owner of Cycloptics, he's a pretty straight-up guy. He isn't a grower or into the mj scene - his target market has largely been "grow chambers" used in horticultural research.
I haven't used HPS for years (decades) but most recently I had been using some pretty high-end LEDs - both the Lumigrow and my own DIY units which utilized the best of the currently-available components at the time. I saw about a 25% uplift in gpw when I swapped over from those to the 315s with no other changes. On a watt-for-watt basis, I think that any of my LEDs would have seriously outperformed HPS. While I'm still adapting to the change in light sources, I anticipate a hell of a lot more before I'm done.
propaganda
in the italian forum "overgrow" u can see 2/3 report about cmh vs hps by customers, not from a seller.....and the response it's much different
indabonga,
Not sure I'm following you. Do you mean to say the customers found the CMH better, or the HPS better? Always good to get multiple points of view on things.
Thanks!
So possibly some conflict of interest with the cycloptics report.
How do the Italian forums find the CMH compares to HPS?
Thanks!
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Where do you see that this report was from a "partner/distributor"? I see no mention of it in the report, and unless Cycloptics has changed their strategy, they were only doing direct marketing.
Also, bear in mind that the Cycloptics reflector is substantially different than any other reflector that is available, so there is more going on here than simply a comparison between 315s and HPS. They are designed to use reflected light almost exclusively, and the grow area needs to be tailored to that concept to take full advantage of the reflector. Their forte is supposed to be very even light with no hot spots or shadowing.
For example, I use Bell Lighting hoods with my 315s and would expect the Cycloptics to outperform them pretty handily in an area that was designed to utilize the Cycloptics. I haven't seen the room design, but 35 lights in an 18'x18' room works out to the lights being on 3' centers, starting 18" from the wall. That room could be used as a surgical suite.
LargePrime
Member
This is the final piece i think.
We need much better and inexpensive reflectors. Or go vert
I've been thinking of getting one of the 1000w Bell hoods and installing a 315 at each end. I'd stick with the glass though, the ventilated fixtures work very well for me and and I've got a bunch of the T9 930s to go through....
LargePrime
Member
also T9's give more lumens per watt. They have no PAR rateing, but one assumes more par too!
Quick question.
I am not in U.S. or E.U., and I want to order domestically.
The only kind of CMH I can find is CDM-TT 400W/840 E40(http://www.ecat.lighting.philips.co...de/master-colour-city-cdm-tt/928485800091_eu/).
Is this the kind of CMH I'd want to use?
Also, I only found Phillips' BSN 400 L300 I ballast. Is this the right ballast? Do I need an ignitor or some other things?
I am not in U.S. or E.U., and I want to order domestically.
The only kind of CMH I can find is CDM-TT 400W/840 E40(http://www.ecat.lighting.philips.co...de/master-colour-city-cdm-tt/928485800091_eu/).
Is this the kind of CMH I'd want to use?
Also, I only found Phillips' BSN 400 L300 I ballast. Is this the right ballast? Do I need an ignitor or some other things?
That lamp is not very well suited as a grow lamp. If you look at the spectral distribution chart at the bottom of the page linked below, you can see that the vast majority of light from it is concentrated near 540nm. This pretty well misses the chlorophyll absorption peaks of 450-465nm and 640-665nm. The 315w CDM puts out about 25% more light per watt, and targets the plants lighting needs much better.
If that is the only local choice for you, yes, it needs a starter. The ballast appears as though it is a match. Note that it requires a 220v input voltage. The lamp doesn't appear to be double-jacketed, so it should probably only be used in an enclosed fixture.
http://www.lumitronlighting.com/lamp/PDF/Metal Halide/MASTERColour CDM-TT.pdf
If that is the only local choice for you, yes, it needs a starter. The ballast appears as though it is a match. Note that it requires a 220v input voltage. The lamp doesn't appear to be double-jacketed, so it should probably only be used in an enclosed fixture.
http://www.lumitronlighting.com/lamp/PDF/Metal Halide/MASTERColour CDM-TT.pdf
Thanks a bunch!
I found one CMH bulb that is 315w:
MASTERColour CDM-TMW Elite 315W
for 50USD
It says either 942 or 930. Please advice.
And the vendor says the matching ballast is:
HID-PV 315 /S CDM
for 80USD
Is this the right one? Do I need anything else with this ballast?
And I do use 220v electricity.
Smoking prices on the 315 gear! Stateside, those lamps range from about $70 to $100, and that is apparently the new ballast - I've only seen pictures of it, no pricing, but the old ballast went from about $200-400.
You need to find out if the lamps are the T9 (single envelope) or T12 (double envelope). The T9 lamps are only appropriate for use in an enclosed hood, and the T12 can be used either open or in an enclosed fixture. CMH lamps operate at very high pressures and can grenade on you, though it is rare. The T12 lamps come with a second jacket, so they can be run open, and this is the style that the "Agro" lamps use.
930 lamps are 3000k, and are best for flowering. The 942 lamps are 4200k and are usually used for vegging, but some people use the 942 for both functions. The Agro version has the red spectrum enhanced for horticultural use, but the other lamps work very well if the Agro isn't available. I use the standard T9 930's with excellent results.
You shouldn't need anything else with the ballast other than an enclosure.
You need to find out if the lamps are the T9 (single envelope) or T12 (double envelope). The T9 lamps are only appropriate for use in an enclosed hood, and the T12 can be used either open or in an enclosed fixture. CMH lamps operate at very high pressures and can grenade on you, though it is rare. The T12 lamps come with a second jacket, so they can be run open, and this is the style that the "Agro" lamps use.
930 lamps are 3000k, and are best for flowering. The 942 lamps are 4200k and are usually used for vegging, but some people use the 942 for both functions. The Agro version has the red spectrum enhanced for horticultural use, but the other lamps work very well if the Agro isn't available. I use the standard T9 930's with excellent results.
You shouldn't need anything else with the ballast other than an enclosure.
If anyone is looking for some of the T9 930 lamps, there are some available on eBay for a good price.
These lamps must be used in an enclosed fixture if you value your safety and real estate.
http://www.ebay.com/itm/PHILIPS-MAS...-E-/151298753936?ssPageName=ADME:B:SS:US:1123
These lamps must be used in an enclosed fixture if you value your safety and real estate.
http://www.ebay.com/itm/PHILIPS-MAS...-E-/151298753936?ssPageName=ADME:B:SS:US:1123
