Your Grandpa's Weed or is UV supplementation really needed?

vintagedvd

Active Member
I wanted better options, but good T5 UV bulbs made outside Europe are almost impossible to buy or are ridiculous expensive. Good fixtures are more available, but not by much. If someone would of told me 3 months ago that I will buy new lights, and T5's on top of that, I would of said he's crazy. I'm not sorry about my purchase, I just hope I didn't throw $100 out the window.

So, from the financial and psychiatric point of view, I could only buy the GT Lightwave T5 2X24W, so I bought it. It comes with 2 stock bulbs that put out almost no UV, so I also bought 2 bulbs of JBL Reptil Sun ; 7500k ; lm 650 ; CRI 90 ; 24W ; UV-A 63% ; UV-B (12%)

I made pictures with the same camera, in the same light conditions, and I've used prescription glasses to measure different levels of UV intensity.

First picture is the control one, lenses without exposure to UV light.


Next picture was made keeping the glasses 10cm(4") below the main light, 4X 50W COB 3070 30G.

I knew it does not produce noticeable UV light, but I was disappointed to see it was true.

Next I tried a regular T8 that I had in the house, with glasses kept at 5cm(2") for 10 minutes.
T8 regular 15W 5cm.jpg
That's what I call barely any UV. A compact CFL bulb at the same distance had the same outcome. I wonder where's the UV in all the indoor growing because I can't find a light that outputs a decent amount of UV. Maybe someone can test a HID, as I don't have one anymore.

Next I wanted to test the Lightwave T5 fixture, so I placed it up side down on a table, and the glasses hanged above it, shined by the fixture. I wanted to hang them at 50cm(20"), but as I hanged them, the lower lens (singular) was at 45cm(18"), and the upper lens was at 55cm(22"). This data is important in the next test.

As you can see, although this test is made a lot farther than the regular T8, a soft tint is visible. The left lens is thicker (long story) so it's not as tinted as the right one, plus it was "shadowed" (I think) by the lens situated lower, between the light and the left lens. What I'm trying to say is that if you take just one of the lenses as reference(preferable the one on the right), you can make use of this experiment. Hope it makes sense. If not, it will in a second.

I changed the stock bulbs with the JBL ones.

Finally, the effects of the UV light were clearly visible, and the difference in the height and chemical composition of the lenses was noticeable in this test. So noticeable that I decided to repeat the test with both lenses at the same height.

Here the difference of the lenses is more visible. I wanted to see the effects on both lenses so I repeated the experiment with both lenses at the same height of 55cm(22"). Unfortunately I was anxious and didn't put the lenses facing down. There is a slight angle, maybe 10°, but they're definitely not facing perfectly towards the light. Still, the lens showed a good amount of UV at twice the distance from the plants that I plan to keep the light.

For a good comparison I took a picture of the glasses under the plain sun (wearing them) for 10 minutes.

This picture was made on the 29.03.2017 at the 46paralel, north hemisphere, between 10:30-10:40 AM

Conclusions:

Considering this test gave results in images instead of numbers, I still consider it a successful experiment. My plan is to have a moderate UV light, that I can keep on the same timer, at the same schedule and at the same height as the main light. These lights seem to fit the bill as I will keep them at around 30cm. I will lower/raise them if I see it needs adjustments and I will post any changes or info that might seem important to this thread. Because of the heat I grow only 2 times a year and never in the summer, even with LEDs, so it might take a wile until I post some actual results, but I promise that I will.
 

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Tim Fox

Well-Known Member
I wanted better options, but good T5 UV bulbs made outside Europe are almost impossible to buy or are ridiculous expensive. Good fixtures are more available, but not by much. If someone would of told me 3 months ago that I will buy new lights, and T5's on top of that, I would of said he's crazy. I'm not sorry about my purchase, I just hope I didn't throw $100 out the window.

So, from the financial and psychiatric point of view, I could only buy the GT Lightwave T5 2X24W, so I bought it. It comes with 2 stock bulbs that put out almost no UV, so I also bought 2 bulbs of JBL Reptil Sun ; 7500k ; lm 650 ; CRI 90 ; 24W ; UV-A 63% ; UV-B (12%)

I made pictures with the same camera, in the same light conditions, and I've used prescription glasses to measure different levels of UV intensity.

First picture is the control one, lenses without exposure to UV light.


Next picture was made keeping the glasses 10cm(4") below the main light, 4X 50W COB 3070 30G.

I knew it does not produce noticeable UV light, but I was disappointed to see it was true.

Next I tried a regular T8 that I had in the house, with glasses kept at 5cm(2") for 10 minutes.
View attachment 3915470
That's what I call barely any UV. A compact CFL bulb at the same distance had the same outcome. I wonder where's the UV in all the indoor growing because I can't find a light that outputs a decent amount of UV. Maybe someone can test a HID, as I don't have one anymore.

Next I wanted to test the Lightwave T5 fixture, so I placed it up side down on a table, and the glasses hanged above it, shined by the fixture. I wanted to hang them at 50cm(20"), but as I hanged them, the lower lens (singular) was at 45cm(18"), and the upper lens was at 55cm(22"). This data is important in the next test.

As you can see, although this test is made a lot farther than the regular T8, a soft tint is visible. The left lens is thicker (long story) so it's not as tinted as the right one, plus it was "shadowed" (I think) by the lens situated lower, between the light and the left lens. What I'm trying to say is that if you take just one of the lenses as reference(preferable the one on the right), you can make use of this experiment. Hope it makes sense. If not, it will in a second.

I changed the stock bulbs with the JBL ones.

Finally, the effects of the UV light were clearly visible, and the difference in the height and chemical composition of the lenses was noticeable in this test. So noticeable that I decided to repeat the test with both lenses at the same height.

Here the difference of the lenses is more visible. I wanted to see the effects on both lenses so I repeated the experiment with both lenses at the same height of 55cm(22"). Unfortunately I was anxious and didn't put the lenses facing down. There is a slight angle, maybe 10°, but they're definitely not facing perfectly towards the light. Still, the lens showed a good amount of UV at twice the distance from the plants that I plan to keep the light.

For a good comparison I took a picture of the glasses under the plain sun (wearing them) for 10 minutes.

This picture was made on the 29.03.2017 at the 46paralel, north hemisphere, between 10:30-10:40 AM

Conclusions:

Considering this test gave results in images instead of numbers, I still consider it a successful experiment. My plan is to have a moderate UV light, that I can keep on the same timer, at the same schedule and at the same height as the main light. These lights seem to fit the bill as I will keep them at around 30cm. I will lower/raise them if I see it needs adjustments and I will post any changes or info that might seem important to this thread. Because of the heat I grow only 2 times a year and never in the summer, even with LEDs, so it might take a wile until I post some actual results, but I promise that I will.
cool test
 

MichiganMedGrower

Well-Known Member
Very interesting.

Not that it is relevant to flourescents. But you did ask about hid and one I used has some decent uv.

The 400 w Hortilux blue metal halide bulb tints my glasses medium dark just working inder it even through the tempered glass of my sealed reflector.

I use a 600w version now but it does not tint the glasses noticeably. I guess it is because the 600 is really a conversion hps bulb as there are no 600 w true mh ballasts.
 

mr. childs

Well-Known Member
I wanted better options, but good T5 UV bulbs made outside Europe are almost impossible to buy or are ridiculous expensive. Good fixtures are more available, but not by much. If someone would of told me 3 months ago that I will buy new lights, and T5's on top of that, I would of said he's crazy. I'm not sorry about my purchase, I just hope I didn't throw $100 out the window.

So, from the financial and psychiatric point of view, I could only buy the GT Lightwave T5 2X24W, so I bought it. It comes with 2 stock bulbs that put out almost no UV, so I also bought 2 bulbs of JBL Reptil Sun ; 7500k ; lm 650 ; CRI 90 ; 24W ; UV-A 63% ; UV-B (12%)

I made pictures with the same camera, in the same light conditions, and I've used prescription glasses to measure different levels of UV intensity.

First picture is the control one, lenses without exposure to UV light.


Next picture was made keeping the glasses 10cm(4") below the main light, 4X 50W COB 3070 30G.

I knew it does not produce noticeable UV light, but I was disappointed to see it was true.

Next I tried a regular T8 that I had in the house, with glasses kept at 5cm(2") for 10 minutes.
View attachment 3915470
That's what I call barely any UV. A compact CFL bulb at the same distance had the same outcome. I wonder where's the UV in all the indoor growing because I can't find a light that outputs a decent amount of UV. Maybe someone can test a HID, as I don't have one anymore.

Next I wanted to test the Lightwave T5 fixture, so I placed it up side down on a table, and the glasses hanged above it, shined by the fixture. I wanted to hang them at 50cm(20"), but as I hanged them, the lower lens (singular) was at 45cm(18"), and the upper lens was at 55cm(22"). This data is important in the next test.

As you can see, although this test is made a lot farther than the regular T8, a soft tint is visible. The left lens is thicker (long story) so it's not as tinted as the right one, plus it was "shadowed" (I think) by the lens situated lower, between the light and the left lens. What I'm trying to say is that if you take just one of the lenses as reference(preferable the one on the right), you can make use of this experiment. Hope it makes sense. If not, it will in a second.

I changed the stock bulbs with the JBL ones.

Finally, the effects of the UV light were clearly visible, and the difference in the height and chemical composition of the lenses was noticeable in this test. So noticeable that I decided to repeat the test with both lenses at the same height.

Here the difference of the lenses is more visible. I wanted to see the effects on both lenses so I repeated the experiment with both lenses at the same height of 55cm(22"). Unfortunately I was anxious and didn't put the lenses facing down. There is a slight angle, maybe 10°, but they're definitely not facing perfectly towards the light. Still, the lens showed a good amount of UV at twice the distance from the plants that I plan to keep the light.

For a good comparison I took a picture of the glasses under the plain sun (wearing them) for 10 minutes.

This picture was made on the 29.03.2017 at the 46paralel, north hemisphere, between 10:30-10:40 AM

Conclusions:

Considering this test gave results in images instead of numbers, I still consider it a successful experiment. My plan is to have a moderate UV light, that I can keep on the same timer, at the same schedule and at the same height as the main light. These lights seem to fit the bill as I will keep them at around 30cm. I will lower/raise them if I see it needs adjustments and I will post any changes or info that might seem important to this thread. Because of the heat I grow only 2 times a year and never in the summer, even with LEDs, so it might take a wile until I post some actual results, but I promise that I will.
i'll be damned, thank you for this test. i have no idea why none of us never thought of doing this. thank you for the inspiration.
 

vintagedvd

Active Member
i'll be damned, thank you for this test. i have no idea why none of us never thought of doing this. thank you for the inspiration.
This is a small thing. Someone was bound to think of this eventually.
I was active on my country forum. I invented a few things in my early days to make our lives better(poor man inventions). I was published 3 times in our magazine. Many of them are obsolete now, or you can find factory products now that do the job as good or better, and they're cheaper to buy. I also made a lot of test and experiments, on different things, that made a few people happier, or at least smarter. But the forum was shut down a wile ago, so I found refuge in international waters.

Cool quote, no?
I forgot to tell, but you reminded me. A perfect spectrum should be totally absorbed by the leaves, so they should look very black under it. It's just a theory, just like UV. What do you guys think?
 
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igothydrotoneverywhere

Well-Known Member
They had new Hortilux T5 bulbs with UVA+B at the last grow show I was at in Jan.

Called "PowerVeg T5 FS+UV"

If UV light was so bad and non helpful, why would the leader in Indoor lighting spend millions on developing a new bulb?

I think we have to look at the origins of the strains we are growing first. The UV at the equator is at its highest and its relative and diminishing quantity can be matched with indigenous strains as you move your finger up the map.

I think in the future grow lights will be tailored to the exact light spectrum of the strain you are growing. Sativas from the equator definitely need UV-B, northern indicas not so much.
 
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whitebb2727

Well-Known Member
I wanted better options, but good T5 UV bulbs made outside Europe are almost impossible to buy or are ridiculous expensive. Good fixtures are more available, but not by much. If someone would of told me 3 months ago that I will buy new lights, and T5's on top of that, I would of said he's crazy. I'm not sorry about my purchase, I just hope I didn't throw $100 out the window.

So, from the financial and psychiatric point of view, I could only buy the GT Lightwave T5 2X24W, so I bought it. It comes with 2 stock bulbs that put out almost no UV, so I also bought 2 bulbs of JBL Reptil Sun ; 7500k ; lm 650 ; CRI 90 ; 24W ; UV-A 63% ; UV-B (12%)

I made pictures with the same camera, in the same light conditions, and I've used prescription glasses to measure different levels of UV intensity.

First picture is the control one, lenses without exposure to UV light.


Next picture was made keeping the glasses 10cm(4") below the main light, 4X 50W COB 3070 30G.

I knew it does not produce noticeable UV light, but I was disappointed to see it was true.

Next I tried a regular T8 that I had in the house, with glasses kept at 5cm(2") for 10 minutes.
View attachment 3915470
That's what I call barely any UV. A compact CFL bulb at the same distance had the same outcome. I wonder where's the UV in all the indoor growing because I can't find a light that outputs a decent amount of UV. Maybe someone can test a HID, as I don't have one anymore.

Next I wanted to test the Lightwave T5 fixture, so I placed it up side down on a table, and the glasses hanged above it, shined by the fixture. I wanted to hang them at 50cm(20"), but as I hanged them, the lower lens (singular) was at 45cm(18"), and the upper lens was at 55cm(22"). This data is important in the next test.

As you can see, although this test is made a lot farther than the regular T8, a soft tint is visible. The left lens is thicker (long story) so it's not as tinted as the right one, plus it was "shadowed" (I think) by the lens situated lower, between the light and the left lens. What I'm trying to say is that if you take just one of the lenses as reference(preferable the one on the right), you can make use of this experiment. Hope it makes sense. If not, it will in a second.

I changed the stock bulbs with the JBL ones.

Finally, the effects of the UV light were clearly visible, and the difference in the height and chemical composition of the lenses was noticeable in this test. So noticeable that I decided to repeat the test with both lenses at the same height.

Here the difference of the lenses is more visible. I wanted to see the effects on both lenses so I repeated the experiment with both lenses at the same height of 55cm(22"). Unfortunately I was anxious and didn't put the lenses facing down. There is a slight angle, maybe 10°, but they're definitely not facing perfectly towards the light. Still, the lens showed a good amount of UV at twice the distance from the plants that I plan to keep the light.

For a good comparison I took a picture of the glasses under the plain sun (wearing them) for 10 minutes.

This picture was made on the 29.03.2017 at the 46paralel, north hemisphere, between 10:30-10:40 AM

Conclusions:

Considering this test gave results in images instead of numbers, I still consider it a successful experiment. My plan is to have a moderate UV light, that I can keep on the same timer, at the same schedule and at the same height as the main light. These lights seem to fit the bill as I will keep them at around 30cm. I will lower/raise them if I see it needs adjustments and I will post any changes or info that might seem important to this thread. Because of the heat I grow only 2 times a year and never in the summer, even with LEDs, so it might take a wile until I post some actual results, but I promise that I will.
Not really a good test.

I get the premise behind it but it is not accurate in anyway.
They had new Hortilux T5 bulbs with UVA+B at the last grow show I was at in Jan.

Called "PowerVeg T5 FS+UV"

If UV light was so bad and non helpful, why would the leader in Indoor lighting spend millions on developing a new bulb?

I think we have to look at the origins of the strains we are growing first. The UV at the equator is at its highest and its relative and diminishing quantity can be matched with indigenous strains as you move your finger up the map.

I think in the future grow lights will be tailored to the exact light spectrum of the strain you are growing. Sativas from the equator definitely need UV-B, northern indicas not so much.
Agromax has a cheaper uv a and b bulb. They also have a 10,000k+uva bulb.

The pure uv bulb with a and b is less than 20 bucks and the uva bulb is less than 10 bucks.

I'm sure the hortilux are good but 30 bucks a pop is a bit pricey.
 

Rocket Soul

Well-Known Member
All good around here, growwise were in between locations, flowering out our last crop now but should have something up in a few months. Good for my growbuddy to get some holidays and to get out of a place with too much history. Hows things your end?
 

Tim Fox

Well-Known Member
All good around here, growwise were in between locations, flowering out our last crop now but should have something up in a few months. Good for my growbuddy to get some holidays and to get out of a place with too much history. Hows things your end?
I have ran so many grows through my grow box i have jars and jars of weed and just smoke myself silly most days hahaha, and with cannabis being legal in Oregon I buy my cloned from the store it's pretty nice
 
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