please you need to learn when to shut up.
while bare cobs do not have a focusing lens on them they are no more diffuse or less than any point source of light.
T5s are diffuse, and an array of tiny leds are diffuse.
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Top bin COB comparison
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while bare cobs do not have a focusing lens on them they are no more diffuse or less than any point source of light.
T5s are diffuse, and an array of tiny leds are diffuse.
REALSTYLES
Well-Known Member
Ok then show me a cannabis grow using mirrors. The cost alone would not be worth the effort on top of that. Can we see some pics of your current grow?Lol, I knew people would go apeshit over the mirrors thing
Yeah people keep saying that, but several people put mirrors in their grow room and with those they get the highest light density. Perfect wall to wall light distribution as well. It's like having a light on the other side of the mirror. Just the way it should be. I don't use mirrors myself, but I did test the reflection and in fact they do reflect better than the walls of my grow tent. Just put a mirror next to your wall and see what it does to the light intensity on your light meter.
Mirrors use aluminium as a reflective material and that's exactly the same as used in most HPS reflectors. Silver would be better of course, difficult to find mirrors with that though and the difference is marginal (apart from the price difference which is huge).
View attachment 3580988
So you are grossly exaggerating the influence on the spectral distribution by mirrors.
That's just plain nonsense. Who's rambling now? Mirrors are perfectly flat. How could they create a hotspot. You must be confused about poorly fixed mylar or something.
Of course there are reflective foils that reflect even better than mirrors, but they are less easy to clean and cost a whole heap more.
What's most important though, get direct reflections and not diffuse. Especially COBs emit diffuse light already.
Rahz
Well-Known Member
It's not a bad theory. People most likely to have tried mirrors in the past would probably be HPS growers. I imagine a mirror surface does a good job at getting all that IR heat down in the canopy and could produce enhance hot spots from a 600+ watt bulb. Maybe it would work better with cobs?
A bunch of mirrors in a grow room sounds like broken glass waiting to happen though.
A bunch of mirrors in a grow room sounds like broken glass waiting to happen though.
AquariusPanta
Well-Known Member
@hillbill
That's my go-to show on Netflix. The scripts for that show are legendary.
@REALSTYLES
It's good that you're growing something with those cob units but the size of those plants, really? I remember growing plants twice as bulky with Lighthouse's early version LED units (Blackstar V1&2 and Chromes V1). I suppose it's not all about size though
@SupraSPL
Hey, mate. I've only performed PAR testing for cobs within tents mainly due to flexibility and ease. It didn't take long for me to conclude that using optics with cobs is practical for most situations involving periods of flowering, as our kind of plants tend to reach 36" inches or more after the beginning of the flowering phase (unless you're realstyles and grow dwarfs) and so direct "penetration" through canopy can obviously be more beneficial than the longer, diffused route of light bouncing off walls, which is what most are ensuing if opting not to utilize optics.
That's my go-to show on Netflix. The scripts for that show are legendary.
@REALSTYLES
It's good that you're growing something with those cob units but the size of those plants, really? I remember growing plants twice as bulky with Lighthouse's early version LED units (Blackstar V1&2 and Chromes V1). I suppose it's not all about size though
@SupraSPL
Hey, mate. I've only performed PAR testing for cobs within tents mainly due to flexibility and ease. It didn't take long for me to conclude that using optics with cobs is practical for most situations involving periods of flowering, as our kind of plants tend to reach 36" inches or more after the beginning of the flowering phase (unless you're realstyles and grow dwarfs) and so direct "penetration" through canopy can obviously be more beneficial than the longer, diffused route of light bouncing off walls, which is what most are ensuing if opting not to utilize optics.
wietefras
Well-Known Member
Where does the idea of a hot spot caused by a mirror come from though? A flat surface cannot cause a hot spot. You'd need some sort of focusing effect to get that. For instance when you hold a sheet of mylar, you will see that it folds up a bit. Those waves in the material will cause a focusing effect in some area's.
It's not just a theory really. Several growers have used mirrors and found it worked much better than what they used before. The guy who tested it built a reflectivity testing device and tested more than a dozen different materials. A mirror foil came out as best and flat white the worst. If we use the mirror foil as the 100% base then a few of the more common materials came out like this:
100% mirror foil
93% 3mm mirror
89% 6mm mirror
70% reflective material from a grow tent
57% diamond foil
53% Orca
49% flat white paint
Basically it came down to this, the more diffuse the reflection, the least of the light would actually go down towards the plants.
Of course that's not the gain you will get over the entire grow area, but it's based on the amount the light from the light source that bounced back off the reflective material. These percentages aren't absolute values either. It's just that the flat white panel gave less than half the light on the light meter in his testing device compared to the mirror foil.
It's really easy to get an indication of how well a mirror works. Just put your light meter near the wall in your grow room and compare the reading you get from just the bare wall itself and when you place a mirror on the wall. If the mirror is small then the best height for it is at a height around half way between the light and the light meter. If you have a flat white wall you won't even need a light meter. The difference will be apparent from the bright spot on the floor.
Heh, yeah you should glue them to the wall or use some other sturdy way of fixing them.
OK and for my next trick, the grey in the middle of the top square is the exact same brightness as the middle of the bottom square:
Just to show how hard things are to believe. Yet still it is true.
Rahz
Well-Known Member
Mirrors do tend to reflect back at an inverse angle, which could place a lot of the extra light towards the center of the tent where the hotspot from the HID was to begin with.
I seem to remember reading various accounts of this phenomena, but perhaps part of my perception comes from mylar sales pitches.
cdgmoney250
Well-Known Member
I think everybody needs to give this a good read through...
https://en.wikipedia.org/wiki/Reflection_(physics)
https://en.wikipedia.org/wiki/Reflection_(physics)
wietefras
Well-Known Member
If you have properly reflective walls a 1000W DE HPS should be covering at least 2m2 (20sqft) or even 5'x5'. So yeah with mirrors in a 4'x4' you would get an overload of light with modern 1000W HPS fixtures.
This is what you get with overlapping fixtures:
Now when you place a mirror to the left of the middle fixture, the light hat would fall outside the wall gets reflected back and produces the light similar to what the overlapping fixture to the left would give:
The light density in the bottom drawing will be similar to what you get with overlapping fixtures. Slightly less actually since you always lose some light with reflections.
KarmaPaymentPlan
Well-Known Member
doesnt that light also have to travel through the glass twice and your banking on that mirror not having any imperfections.
mirrors and mirroring surface are 2 very different materials
wietefras
Well-Known Member
Indeed. That's why the miror foil worked better in getting light to the plants. Also why the 3mm mirror worked better than the 6mm mirror.
His choice for mirrors was based on them being easier to clean and install. You just wipe the glass and you are good to go. He put kit around them so the whole thing is water tight and bug tight. No place for critters to hide themselves or their eggs
Mirror foils are a difficult to get perfectly flat on the wall and if you get that wavy look in them you might get hot spots.
littlejacob
Well-Known Member
Bonjour
I am really happy with my crop...it was a Amherst sour diesel...sorry...the trainwreck is a bit bigger!
The smallest buds are on the moby dick but there is more because it is the tallest (2 feet...but 1.5 feet large)
I will reorder soon and will make pics of my build...but I just copy other buildings! Best Choice of models: supraspl/greengene/realstyle/rhaz/growmau...etc...and all those who helped me and they are too many to name them all...THANKS AGAIN mes amis!...so yes I will take pics of the 8/10 individual cob panel I am about to make...this way I will have 5 cxb3590@1400mA in a 3.5x3.5x4.5 and 9 in a 4x4x7(2 hlg-240-1400b and 1 hlg-185-1400b)...plus 9 cxa 2530/40 5000ºk on an hlg-185-700b for vegg!
Next grow I will add 10 more...and then I will skip to 1050mA...1 cob over each sq/ft! Not 1 cob per sq/ft!!! 1 OVER EACH SQ/FT!
It was the first time I used only amendments...Plagron batmix soilbag40%/coco ugrow with trichoderma30%/ewc 20%/perlite vermiculite 10% plus bat guano bloom and flour worm guano (very high NPK...strong shit...lol!...really crazy!) All amendments are from www.terralba.com it is a french site and since I am pretty happy I will reorder and add a few thing maybe (I wait for smoke test...but smell test approved! )
As for the grow style...it is bending pinching and training
When the plant have 5 real pair of leaves I put her at 180º...I attach the base of the plant on a side of the pot and I bend her at the opposite...then I pinch a tiny bit to turn all the leaves in the same direction (always 1/4 of turn in the same sens this way the leaves and branches will grow on the sides of the plant!) If you do that you do not need to cut anything...just pinch the main branch and the fastest one to let the others grow...it is not easy to explain I will make pics of the naked plant...I attach every branch on the side of my plastic pot to open the middle of the plant! (It is like a spine and the lamb...thinks we have on our sides...I will take some pics!)
Pics speak a better English than me!
CU
hillbill
Well-Known Member
Those sliding glass doors will be much easier than those zippers.
May not have been tried with LEDs or cobs so what the hell! But you could just mount cobs around the perimeter at several levels even. Those horizontal cobs might get a lot of light to the wonderful flowers themselves. Light from 5 directions. Heat dissipation may take some innovation.
Another little thought. Those here are quite aware of technical advances in SS lighting and hydro or dirt or cmh, but May have not spent any time on mirror advances. With all the solar energy research happening, who knows?
A cinema where I lived when a kid had mirrors on opposing walls and so the infinite diminishing reflection. Spooky, but was that diminishing?
Would be absolutely beautiful and could be good enough and way easy to clean. There really are other values to each grower beyond just the highest possible efficiency. Like being free of Blurple Affective Disorder (BAD). Never ever liked that damn warehouse yellow either. Much happier these days.
May not have been tried with LEDs or cobs so what the hell! But you could just mount cobs around the perimeter at several levels even. Those horizontal cobs might get a lot of light to the wonderful flowers themselves. Light from 5 directions. Heat dissipation may take some innovation.
Another little thought. Those here are quite aware of technical advances in SS lighting and hydro or dirt or cmh, but May have not spent any time on mirror advances. With all the solar energy research happening, who knows?
A cinema where I lived when a kid had mirrors on opposing walls and so the infinite diminishing reflection. Spooky, but was that diminishing?
Would be absolutely beautiful and could be good enough and way easy to clean. There really are other values to each grower beyond just the highest possible efficiency. Like being free of Blurple Affective Disorder (BAD). Never ever liked that damn warehouse yellow either. Much happier these days.
BuddyColas
Well-Known Member
Your English is good. Very understandable. I am a Uni-Lingual American, so anyone who puts the effort into learning a new language…and uses it, has my respect. I will look forward to your pictures (understandable in all languages!).
I too have learned much from the very individuals you mentioned. I am on my first build and grow since moving from HPS growing to COB growing.
Thanks for sharing about your grow. So if I got it right, you are growing under a combined 23 cobs. A good size garden for sure. I have a grow cabinet of 8 square feet under 8 Vero 29s in a closet.
You have given me some ideas. I have always topped for 4-6 main branches, tie them horizontal and cut off the downward facing branches. So 25% of the branches get the snips. I already give my branches a little “massage” so to speak…supercropping and twisting them so they can heal and grow bigger buds. But next time I will try your method and twist them ¼ turn like you and see how that goes. I can visualize it already.
You bend, pinch and train. Very similar to the “5 T’s of Cannabis Growing.” Top ‘em, train ‘em, tie ‘em, trim ‘em, and ugh…ugh…ugh…toke ‘em! Yeah!
Thanks again for sharing and I look forward to your pictures.
littlejacob
Well-Known Member
Bonjour
You see my bad English...
Atm I only have 4 cxb3590 3500ºk CD on an hlg-185-1400b...220w no more...my kill a watt say 211w...!
But I will reorder in a few weeks 8 or 10 more cob...10! Or depending on shipping prices 12 cob + 3 hlg-185-1400 or 10 + 2 hlg-240-1400b!!???
And more in 3 month!
I still have a 600hps and it will be my last hps grow...cut in a week or 10 days except the cheese that I have to chop in 2 days...no more water till chop...I water then 1h later I chop! It is to increase curing time!
I never top plants...never...I just remove the first pair of branches and the really first one before I repot and put it underground and after I use all the others...180º...every branches goes on the left and on the right...the first you bend it at the opposite of the main cola(middle back) after middle corners /sides middle/ forward corner and main cola but if you have a big pot you can have more top bud...I have 11/13 top bud on each plants!
You will need a lot of plastic with metal in it (it is green and you can cut it at the disired size)or anything to bend and pinch pinch and pinch to create an uniform canopy!
Pics soon to illustrate my poor words...I just need to buy an english-french dictionary and keep it close cause I really have a lack of vocabulary...I often look for some words that I don't know or forget because I didn't use the terms often!
CU
You see my bad English...
Atm I only have 4 cxb3590 3500ºk CD on an hlg-185-1400b...220w no more...my kill a watt say 211w...!
But I will reorder in a few weeks 8 or 10 more cob...10! Or depending on shipping prices 12 cob + 3 hlg-185-1400 or 10 + 2 hlg-240-1400b!!???
And more in 3 month!
I still have a 600hps and it will be my last hps grow...cut in a week or 10 days except the cheese that I have to chop in 2 days...no more water till chop...I water then 1h later I chop! It is to increase curing time!
I never top plants...never...I just remove the first pair of branches and the really first one before I repot and put it underground and after I use all the others...180º...every branches goes on the left and on the right...the first you bend it at the opposite of the main cola(middle back) after middle corners /sides middle/ forward corner and main cola but if you have a big pot you can have more top bud...I have 11/13 top bud on each plants!
You will need a lot of plastic with metal in it (it is green and you can cut it at the disired size)or anything to bend and pinch pinch and pinch to create an uniform canopy!
Pics soon to illustrate my poor words...I just need to buy an english-french dictionary and keep it close cause I really have a lack of vocabulary...I often look for some words that I don't know or forget because I didn't use the terms often!
CU
littlejacob
Well-Known Member
Bonjour
I was about to buy an orca tent!
But now I am not so sure...orca is supposed to be better than mylar if you lesson to secret jardin but I heard many bad comment on orca...and only
2 good...and one guy said it rise is gpw by 20/30%!???...too good to be true!
CU
I was about to buy an orca tent!
But now I am not so sure...orca is supposed to be better than mylar if you lesson to secret jardin but I heard many bad comment on orca...and only
2 good...and one guy said it rise is gpw by 20/30%!???...too good to be true!
CU
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