Anyone growing or familiar with CMH?

[Dr Fish]

The footprint on the 315 is at best 3'x3', and unless you look at the bulb itself, i doubt there's much risk of getting exposed to very much uv.. If the lights are close together i turn then both off till they cool down, and run an incandescent light bulb... being off for 15 minutes doesn't affect the cycle, veg or flower.. Always doing a scrog screen, the only stretch you'll get during flower is predetermined by the genetics of the plant .. That's what i love about scrog...
The stretch you get in veg is pulled back down under the screen till you flip... I did a Blackberry and a Blue mystic at the same time, under separate lights... The stretch for the BB was about 12", the Blue Mystic was 30"+... I never veg more than 5 weeks till 12/12.. Running rdwc i find i can fill a screen in that length of time..

 

[Komplex180]

Thanks. So any CMH is as good as another? Or are you just saying that Philips is the main manufacturer?
The warnings about not working in the room while the bulbs are on- to avoid risk of radiation- sound like a bit of a deal breaker for me. On the other hand - I think what they're referring to is only if you break an bulb while it's on, which seems unlikely. Any thoughts on this?

Both actually. Most people that I've seen using CMH use the Phillips regardless if they were pieced together systems or one of the popular kits(SunSystem, Phantom, etc.) I actually saw a video of a comparison of CMH bulbs as well and Phillips came out on top, the only con was that it was more expensive than than the others.

I'll try and find the link

 

[Weaselcracker]

So would a couple 315s be a good upgrade from a 600w HPS for flowering despite maybe(?) the spectrum being a bit more suited to veg growth

And I have to say that reading the warning 'do not be in the room while the lights are on' does bother me.

 

[Komplex180]

Here's the link to the comparisons

Ceramic Metal Halide CMH 315W Lamp Comparison Test Data & Review - Growers House Review Lab

 

[Komplex180]

So would a couple 315s be a good upgrade from a 600w HPS for flowering despite maybe(?) the spectrum being a bit more suited to veg growth

They say a 1 315w can get you the same as a 600w hps(doubtful) but 630 will definitely kill a a similar wattage hps.

 

[Komplex180]

Sorry I probably could have put this all in one post but I keep remembering things from my research.

CMH is also more efficient in terms of electricity:useable light. They also have better PAR ratings, UV production, and (not production related) shows the natural colors of the plants better.

 

[Weaselcracker]

I've read through quite a few pages on them in the last day. They sound great. I'm still a bit unclear on this idea of dangerous UV-c radiation- dangerous unshielded bulbs vs shielded ones- which ones are shielded and which ones aren't. Why would anyone sell unshielded bulbs..?
Don't get me wrong I'm not usually paranoid about stuff like this. I just like to spend quality time in my grow without frying or turning blind.

 

[Slicknick909]

I've read through quite a few pages on them in the last day. They sound great. I'm still a bit unclear on this idea of dangerous UV-c radiation- dangerous unshielded bulbs vs shielded ones- which ones are shielded and which ones aren't. Why would anyone sell unshielded bulbs..?
Don't get me wrong I'm not usually paranoid about stuff like this. I just like to spend quality time in my grow without frying or turning blind.

Monster gardens YouTube channel has some pretty great comparisons and reviews on the CMH bulb that should help clear up any concern, they've saved me a bunch after watching the DE HPS comparisons, I just thought philips was the go to since basically invented it, I was wrong though!

 

[omega83]

I've read through quite a few pages on them in the last day. They sound great. I'm still a bit unclear on this idea of dangerous UV-c radiation- dangerous unshielded bulbs vs shielded ones- which ones are shielded and which ones aren't. Why would anyone sell unshielded bulbs..?
Don't get me wrong I'm not usually paranoid about stuff like this. I just like to spend quality time in my grow without frying or turning blind.

Cmh is pretty safe..just if your going to work under them for 20min or more put sume sun glasses on....cmh is the best way to go....theirs a reason why some of the best growers in the world switched to cmh...better for veg and flowering..

 

[Komplex180]

Wow! Now that I think about it, I've seen a lot of commercial growers switching to cmh

 

[omega83]

Wow! Now that I think about it, I've seen a lot of commercial growers switching to cmh

A buddy gave me 6 of cks's white cookies to see how well they would do under my 315 cmh lights because he has used every light u can think of..and he has over 30 years of growing under his belt..so i sent him these pics of the seeds he gave me..he left to the hydro shope to buy 16 of the lights to switch over..lol..today is day 20 from seed..getting big fast..very green,healthy and happy...

 

[schomegrown]

A buddy gave me 6 of cks's white cookies to see how well they would do under my 315 cmh lights because he has used every light u can think of..and he has over 30 years of growing under his belt..so i sent him these pics of the seeds he gave me..he left to the hydro shope to buy 16 of the lights to switch over..lol..today is day 20 from seed..getting big fast..very green,healthy and happy...

Damn right! I'm getting ready to do my very first auto under my 630. Gonna try to make that thing explode! Thanks for sharing those they look great.

 

[Komplex180]

A buddy gave me 6 of cks's white cookies to see how well they would do under my 315 cmh lights because he has used every light u can think of..and he has over 30 years of growing under his belt..so i sent him these pics of the seeds he gave me..he left to the hydro shope to buy 16 of the lights to switch over..lol..today is day 20 from seed..getting big fast..very green,healthy and happy...

Of course he did, you can argue with results lol.

I wanna play too!

Day 31

the one on the right is 22in tall, the left one is 18in.

 

[schomegrown]

Haven't been on in a while so figured I'd update on how my CMH 630 is doing. I am growing LemonGarlicOG, OriginalBubblegum, and GrizzlyPurpleKush. I am in week 4 of flowering or 31 days as of today. Very happy with the penetration this light has! I am running my light at 700w with the 3200k full spectrum bulb. Definitely considering getting another one of these lights very soon.

 

[Beleaf]

So is there a consensus on what system would be the best in terms of reliability and safety? I'd like to switch to a 630 from my hps.

Any thoughts on Dimlux?

 

[schomegrown]

So is there a consensus on what system would be the best in terms of reliability and safety? I'd like to switch to a 630 from my hps.

Any thoughts on Dimlux?

I haven't heard of Dimlux yet. I have a SunSpectra 630w CMH. Most the reviews and designs I have read and seen are very similar. I have yet to have any kind of issues with my light at all. My light came with a remote and every thing to hang it. It also has 300w, 400w, 630w, and 700w which I love! I would say just read lots of reviews.

 

[Beleaf]

I haven't heard of Dimlux yet. I have a SunSpectra 630w CMH. Most the reviews and designs I have read and seen are very similar. I have yet to have any kind of issues with my light at all. My light came with a remote and every thing to hang it. It also has 300w, 400w, 630w, and 700w which I love! I would say just read lots of reviews.

Thanks! I'll look at that system.

 

[ShiggityFlip]

CMH are about 140 lm/w and quantum boards and cobs can hit 180+lm/w.
That doesn't mean I don't like CMH. I have 5 of them. But they won't match the efficiency of Samsung Lm561c based boards. I am building some 520W board setups and now have the CMH for veg and emergencies.

That being said if I couldn't afford cobs or boards I would still
Be happy with my CMH until I could afford them.

 

[ShiggityFlip]

One of the benefits of cobs and boards is spreading out the light.

This is one of my 520W setups that matches the photon output of a SE 1000W hps. It also hits the plants from more angles. More angles means less shadows so better total photosynthesis.

 

[ShiggityFlip]

Still CMH can produce very nice results. This bud is from under a phillips 3100k 315 CMH

top bud is Dynastygenetics Bluniverse. Bottom dried bud is BOG sour bubble that took the July Nug of the month! Here is that sour bubble in flower.