Flowering with Cree bulbs

Shwagbag

Well-Known Member
I have some old Spectras that work well for vegging but I don't really need to run 140-180 watts if I can do it with 80-ish and with a larger footprint. For some reason I really like the idea of these!
 

captainmorgan

Well-Known Member
Hmmmm. As I understood it you had to upgrade the ballast to an electronic ballast. The Cree website says its compatible with 90% electronic ballasts.

Found this cool link - Cree T8 Review
Yea,that site has reviews and tear downs of all the Cree home depot stuff. These would be great if you had a compatible fixture you could use them with. The problem I see is the newer gens of cree LEDs make them a less efficient option but if you already have a fixture they will work with, it's a cheap and easy upgrade.
 

Shwagbag

Well-Known Member
Last post here and I will move the discussion here so I don't spam this flowering thread any more.

I've never used T8's. I've used 8 and 4 bulb T5's which work great. I replaced the 8 bulb with (2) 120 W LED's which run about half the power, and my 4 bulb fixture pewped out. These would replace my 4 bulb fixture nicely.

I see what you're saying Cap'n, but do you think they will translate this tech into T5? Seems awful small for this kind of build but you just never know.

Have you guys seen these before? I found these in my random surfing and they're priced at $125 Cree SL Series. Unfortunately, they're only available in 3500K at the moment.
 

captainmorgan

Well-Known Member
Last post here and I will move the discussion here so I don't spam this flowering thread any more.

I've never used T8's. I've used 8 and 4 bulb T5's which work great. I replaced the 8 bulb with (2) 120 W LED's which run about half the power, and my 4 bulb fixture pewped out. These would replace my 4 bulb fixture nicely.

I see what you're saying Cap'n, but do you think they will translate this tech into T5? Seems awful small for this kind of build but you just never know.

Have you guys seen these before? I found these in my random surfing and they're priced at $125 Cree SL Series. Unfortunately, they're only available in 3500K at the moment.
This discussion is on track for why this thread was started. Was the $125 for the 55 watt version? I guess it comes down to how much space your using these last two lights your looking at. In a small space it's quick and easy to use these but for a larger space these LEDs are a lot less efficient than the newer LEDs you could DIY or even buying a couple panels that offer newer gen LEDs.
 

Shwagbag

Well-Known Member
This discussion is on track for why this thread was started. Was the $125 for the 55 watt version? I guess it comes down to how much space your using these last two lights your looking at. In a small space it's quick and easy to use these but for a larger space these LEDs are a lot less efficient than the newer LEDs you could DIY or even buying a couple panels that offer newer gen LEDs.
Thanks Cap'n. The linear lights appeal to me because they're low wattage, plug and play, long lasting and provide a nice wide footprint at a close distance. They're ideal for early veg in a short box. The more I look at it the more appealing that fixture Someguy has looks to me :p

Since my 4' x 4 bulb T5 fixture burnt out I've been running single fixture T5's x 3. It does the job for now and its paid for lol, so I'm in no hurry. Just talking and learning!

Yes, $125 for the 55w version. I don't think I'm interested in the 3500K though, which is the only option.

This video was pretty cool! LED - Cree CR Series.
 

captainmorgan

Well-Known Member
Thanks Cap'n. The linear lights appeal to me because they're low wattage, plug and play, long lasting and provide a nice wide footprint at a close distance. They're ideal for early veg in a short box. The more I look at it the more appealing that fixture Someguy has looks to me :p

Since my 4' x 4 bulb T5 fixture burnt out I've been running single fixture T5's x 3. It does the job for now and its paid for lol, so I'm in no hurry. Just talking and learning!

Yes, $125 for the 55w version. I don't think I'm interested in the 3500K though, which is the only option.

This video was pretty cool! LED - Cree CR Series.
The XGS 190 uses 3750k and does a nice job vegging so you don't need 6500k unless your trying to keep your node spacing very tight. My party cup plant was grown under a 3000k from seed,I had some serious stretch but part of that was the strain. I saw a grow from Stardustsailor with two plants from seed under one of his DIY lights that was 3000k and they were very bushy and not stretched out. I got some 4000k Cree CXA COBs just for my veg area but I haven't had the extra time to put them together yet.There are T5 LED tubes but not made by Cree.
 

Shwagbag

Well-Known Member
I always like to keep my node spacing tight! :D I'd be happy with 5k for early development. For now its (2) 6500K T5's and (1) 4500K. I'm gonna peep those T5 LEDs thanks!
 

TubePot

Well-Known Member
If I remember right the Cree T8 tubes were meant for retrofits and work with the existing ballasts,I thought there was a compatibility list for the ballasts.
Correct.

From the second sentence of the above link
These lamps go into an existing fluorescent light fixture and run off of the fluorescent ballast. Cree says they are compatible with 90% of the existing fluorescent T8 fixtures, even dimmable ones.
 

GreenThumbsMcgee

Well-Known Member
bulb 1.png bulb 2.png
hey all...I have been using cree bulbs now for about my last two grows. I am just doing one at a time for personal smoke, in my homemade little grow box, so I have been battleing heat issues since I first started trying to grow in this thing....started with CFL's, to hot. moved on to these new cree style with a built on heat sink, and they cut down the heat drastically, and I have been using those the last two grows, and they have done their job. I think flowering they could had been better when it comes to light penetration, as it will grow some thick buds, but I just don't feel like it gets it quite all the way done....don't get me wrong, you can get some great smoke, and pretty tight buds at that, it just feels a little "half cooked" if you will, but that's not my issue anyway....I was at home depot the other day, and noticed after I was there just 6 months ago, and bought oh, say$200 in bulbs, just to turn around and see these newest "new" ones, and bought a few, they are freaking awesome IMO. Yes they have less warrenty, and yes, they feel flimsy, but side by side, they put out the same amount of lumens, and they are still side firing style bulb, they run a HELL of a lot cooler then the ones I JUST bought!!! I now want to run all these style, and I am sure my box would be running perfect temp closed, or open door. that says a lot, cause I have lost a plant when I didn't open the door for 8 hours once, with CFL's, and it got to about 120F and killed my baby. that's where the heat battle began. I am satisfied with wat I got, but I tell ya, these new ones are more disposable, and cheaper, wont last as long, but they put out a shit load of light with little heat. seems to be a win win, just gotta replace them more often.
well, that is my take on them, but I still haven't USED the newest style for a grow, I am curious if any of you guys have tried them and what you think of them.
I have been toying with the idea of building a led light board using the diodes of the bulbs, and these newest ones are practically taken apart already, I don't think it would be to hard, and you could get a fucking shitload of light outta putting 20 of them diodes on a board....
that again, is another topic, I just really want to know how they work, if they are as good as their predecessor and etc etc....
thanks guys.
 
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First time grower/poster here. Finally finished reading this thread in prep for my 1st grow. Props to Captainmorgan and all the contributors for all the amazing info and advice. I feel like I've been growing for years! Don't worry, I'm sure Mother Nature will kick me in the nads a few time to show me who's boss.

For Canadian members, Rona (Canada's answer to Home Depot) has all LED light bulbs on sale for $2 off, each bulb, any brand they carry. After the Ontario rebate coupons that they also kindly printed out I was able to get 10 of the Facto (house brand) 9.8w 2700k bulbs for less than $4 per, taxes in. Thought it might be helpful.
 

az2000

Well-Known Member
FYI: I made a flexible top-light fixture for Cree PAR38 (18w) spotlights:
Yesterday I harvested a plant flowered under that fixture (and sidelight using 9.5w Cree A19 bulbs):

IMG_20150305_162533.jpg

IMG_20150305_162351.jpg

Details about the grow were posted here.

One thing I'd like to emphasize is that the plant flowered under only 18-22w/sq ft. I intended to be around 30. The plant turned out larger than I expected. I chose not to add light because I wanted to be able to interpret the results to as few variables as possible.

I've grown under 21w/sq ft with a rebranded Chinese import (Blackstar 135w UFO) which I bumped up to 32w/sq ft using Cree lightbulbs as sidelight. So, I know how those light levels compare. I can say these lights at 21w/sq ft did better than the Blackstar when I ran it at 21w/sq ft. I'm confident these lights would have done excellent if I used more to get 30w/sq ft.
 

PSUAGRO.

Well-Known Member
Yesterday I harvested a plant flowered under that fixture (and sidelight using 9.5w Cree A19 bulbs):

View attachment 3366010


Details about the grow were posted here.

One thing I'd like to emphasize is that the plant flowered under only 18-22w/sq ft. I intended to be around 30. The plant turned out larger than I expected. I chose not to add light because I wanted to be able to interpret the results to as few variables as possible.

I've grown under 21w/sq ft with a rebranded Chinese import (Blackstar 135w UFO) which I bumped up to 32w/sq ft using Cree lightbulbs as sidelight. So, I know how those light levels compare. I can say these lights at 21w/sq ft did better than the Blackstar when I ran it at 21w/sq ft. I'm confident these lights would have done excellent if I used more to get 30w/sq ft.
Very nice az..........enjoy your harvest.
 
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