PCBuds
Well-known member
That was fricken cool !!
Garbage day is Friday for me so I'm gonna cruise the neighborhood Thursday night to look for old TV's/monitors.
-
Happy Birthday ICMag! Been 20 years since Gypsy Nirvana created the forum! We are celebrating with a 4/20 Giveaway and by launching a new Patreon tier called "420club". You can read more here.
-
Important notice: ICMag's T.O.U. has been updated. Please review it here. For your convenience, it is also available in the main forum menu, under 'Quick Links"!
Off the shelf retail store screw-in LED and CFL bulb comparisons
- Thread starter blynx
- Start date
That was fricken cool !!
Garbage day is Friday for me so I'm gonna cruise the neighborhood Thursday night to look for old TV's/monitors.
E
ESTERCHASER
macguyver boards!
macguyver boards!
my wheels are hitng mach 1 WHAT A VIDEO! MORE PLEASE!
macguyver boards!
my wheels are hitng mach 1 WHAT A VIDEO! MORE PLEASE!
In theatrical lighting fresnel instruments have been used for years to diffuse or concentrate light. By moving the light source further away from the lens you can create a concentrated spot of light, while moving the source closer to the lens creates a more dispersed area of less intense light. I have a bunch of these old instruments floating around and rarely get use. Some lighting designers still swear by them though.
https://en.wikipedia.org/wiki/Fresnel_lantern
https://www3.northern.edu/wild/litedes/ld06.htm
Hookahhead
Active member
Remember when we were talking about the filament based SILs? Tonight I found another video by the same guy who did the other great video on the filaments. In this video he builds his own SIL! Something that I thought was interesting, around 1:30 he is drawing a circuit diagram. That little diode on the neutral side we’ve been speculating about, f-e was right it’s an “inrush current limiting resistor”. At 17:55 he discusses a using a 1 megaOhm discharge resistor to limit voltage spikes.
https://m.youtube.com/watch?v=AkL72XVtKew
https://m.youtube.com/watch?v=AkL72XVtKew
PCBuds
Well-known member
Hookahhead sent me this link to a great listen.
https://podcasts.apple.com/us/podca...-science-podcast/id1258365194?i=1000429256638
Interesting, she mentions that a 660 Watt LED light for a greenhouse costs ~$1200.
We can use SlLs for less than $2 each and $2 for sockets and wire.
$4 for 10 Watts is only $264 for 660 Watts.
I think she's getting ripped off.
https://podcasts.apple.com/us/podca...-science-podcast/id1258365194?i=1000429256638
Interesting, she mentions that a 660 Watt LED light for a greenhouse costs ~$1200.
We can use SlLs for less than $2 each and $2 for sockets and wire.
$4 for 10 Watts is only $264 for 660 Watts.
I think she's getting ripped off.
PCBuds
Well-known member
If you use good led strips with a quality Meanwell driver, you won't need inrush or outrush protection.
The driver will take care of that, especially if it's plugged into a surge protector.
But if the power goes out you might be in trouble.
Hookahhead
Active member
Some more juicy tid bits in this one, such as the capacitor on the back of PCBuds boards. He also discusses how the boards will current regulate themselves if they get too hot. This means all of us SIL growers should be thinking about keeping our bulbs cool to keep them running at full power.
I really enjoy this guy, but I should probably be doing other things than watch him take shit apart.
https://youtu.be/YeWnHnZ-ojw
I really enjoy this guy, but I should probably be doing other things than watch him take shit apart.
https://youtu.be/YeWnHnZ-ojw
PCBuds
Well-known member
I like watching it too, but he really needs to blow something up.
It would be way more entertaining..
I wanna see sparks and magic smoke. Lol
Oh, no way in hell. Traditional theatrical lights are quite hot. I was speaking more to the older more traditional use of the fresnel lens, which in fact was designed for lighthouses. The lamps in the theatrical fresnel instruments are not what we would consider efficient. There are some newer lamps made for ETC's newer version of the fresnel, called parnel (a hybrid of Par 64 instruments and fresnel instruments), which use a HPL lamp. The old fresnel theatrical fixtures use this type of lamp..
Maybe in the short run the SILs are less expensive, but you also have to thing about efficiency in the long run. I'm considering getting a 150w dimmable QB kit for around $170, but the lumens/watt are much better than any SILs available near me.
https://horticulturelightinggroup.com/collections/all/products/135w-qb-v2-led-kit
Attachments
36w screw in led
36w screw in led
Just ordered 2 of these to test suspiciously cheap.smd2835
https://www.lazada.co.th/products/s...QjaMPZHeD0sLNev_qeued7-AxOw6zUERoCP-cQAvD_BwE
36w screw in led
Just ordered 2 of these to test suspiciously cheap.smd2835
https://www.lazada.co.th/products/s...QjaMPZHeD0sLNev_qeued7-AxOw6zUERoCP-cQAvD_BwE
Hookahhead
Active member
So I was looking more into this fresnel lens/ LCD screen thing. A fresnel lens is great at concentrating a large area of light into a much smaller, more intense beam (solar death ray). Of course it also works in reverse, taking a small, intense light source and spreading it out over a larger area (Old projection TVs). Using it in “reverse” might be something to consider for COB LEDs to “smooth out” the light intensity directly under them. However, this doesn’t seem practical for SIL, strip, or board style grows as the light is already spread out..
Then I came across a recent post on an electronics board that brings the same video into question. The thread suggests that the LCD does not contain a fresnel lens, but instead possibly a prism sheet known as BEF (Brightness enhancement film).
https://forum.allaboutcircuits.com/threads/do-all-lcd-tvs-have-a-fresnel-foil-even-big-or-hdr-tvs.163090/
As the video crono posted suggests, there are 2 types of LED LCD screens. Ones that use a single strip (or two) of lights mounted on the edge, or ones that have multiple LEDs distributed evenly over the backside. Because they function slightly different, I would expect the filtering sheets to be different. The photo above illustrates the first type, like the one shown in the video. The light is first spread out using internal reflection until it passes through the small holes in the “light guide plate”. The effect is that the end of the screen opposite of the light source is nearly as bright as end closest to the light source.
The first minute of this video provides a great explanation of the different layers in an edge lit display. He verifies that the “fresnel lens” is actually a prism film. This guy seems like he knows what he’s talking about so I’ll take his word for it.
https://youtu.be/jiejNAUwcQ8
So what does the prism sheet actually do? From what understand, it redirects/recycled light that would be lost at the edges to be more perpendicular to the screen, thereby directing more photons out the front towards the viewers and increasing perceived brightness.
I have yet to determine if this would be beneficial to a SIL, strip, or board style grows. My gut instinct says yes, other grow light manufactures have shown us that by lensing the chips (which normally have a 120 degree beam angle), we increase penetration by pushing more photons “down” into the canopy.
3M and other companies produce this film, and sheets of various sizes are available for on amazon or eBay. Here’s a spec sheet I found, apparently they can be doubled up for greater effect!
https://multimedia.3m.com/mws/media/721803O/vikuititm-brightness-enhancement-film-bef-iii.pdf
Then I came across a recent post on an electronics board that brings the same video into question. The thread suggests that the LCD does not contain a fresnel lens, but instead possibly a prism sheet known as BEF (Brightness enhancement film).
https://forum.allaboutcircuits.com/threads/do-all-lcd-tvs-have-a-fresnel-foil-even-big-or-hdr-tvs.163090/
As the video crono posted suggests, there are 2 types of LED LCD screens. Ones that use a single strip (or two) of lights mounted on the edge, or ones that have multiple LEDs distributed evenly over the backside. Because they function slightly different, I would expect the filtering sheets to be different. The photo above illustrates the first type, like the one shown in the video. The light is first spread out using internal reflection until it passes through the small holes in the “light guide plate”. The effect is that the end of the screen opposite of the light source is nearly as bright as end closest to the light source.
The first minute of this video provides a great explanation of the different layers in an edge lit display. He verifies that the “fresnel lens” is actually a prism film. This guy seems like he knows what he’s talking about so I’ll take his word for it.
https://youtu.be/jiejNAUwcQ8
So what does the prism sheet actually do? From what understand, it redirects/recycled light that would be lost at the edges to be more perpendicular to the screen, thereby directing more photons out the front towards the viewers and increasing perceived brightness.
I have yet to determine if this would be beneficial to a SIL, strip, or board style grows. My gut instinct says yes, other grow light manufactures have shown us that by lensing the chips (which normally have a 120 degree beam angle), we increase penetration by pushing more photons “down” into the canopy.
3M and other companies produce this film, and sheets of various sizes are available for on amazon or eBay. Here’s a spec sheet I found, apparently they can be doubled up for greater effect!
https://multimedia.3m.com/mws/media/721803O/vikuititm-brightness-enhancement-film-bef-iii.pdf
E
ESTERCHASER
lighting disertations from cannabis growers...im in heaven right?
PCBuds
Well-known member
I was thinking of removing the lenses and using the old TV as grow light?
EDIT: I think I mean just the LCD layer ?
But then I checked the back of my 32" (diagonally) flat-screen TV and it said "Maximum Power Consumption 60 Watts" so it probably wouldn't be putting out very many lumens.
As far as my LED strip goes, I was thinking of filling some sort of skinny container with distilled water to use it as a coolant but my strips have exposed metal on the edges of each LED segment that I'm sure would eventually corrode and contaminant the water then the water would start to conduct electricity and turn cloudy.
Trying to seal up the edges of 56 tiny LED segments would be a PITA.
Plus I would need a separate driver for just that strip because I would want to crank it right up to max.
I think I'm going to give up on my homemade, water-cooled LED idea.
Last edited:
Hookahhead
Active member
I haven’t ever seen water cooling the actual diode. However I have seen setups where people use square aluminum channels, and run water through that. The LEDs would be mounted directly to the aluminum.
PCBuds
Well-known member
I was figuring the strip was all waterproof material except the exposed solder.
I remember seeing solder joints on circuit boards where they turn white with corrosion from moisture.
I'm assuming the top surface of the LED is plastic too?
That means the whole strip could be submerged even in regular water.
If that's the case then the water can pull heat right from the surface of the LED and keep the hottest point cooler.
The water in the sealed container would eventually heat up but it would radiate its heat to the surrounding air through the glass or plastic container and there would be lots of surface area to do that.
I remember seeing solder joints on circuit boards where they turn white with corrosion from moisture.
I'm assuming the top surface of the LED is plastic too?
That means the whole strip could be submerged even in regular water.
If that's the case then the water can pull heat right from the surface of the LED and keep the hottest point cooler.
The water in the sealed container would eventually heat up but it would radiate its heat to the surrounding air through the glass or plastic container and there would be lots of surface area to do that.
PCBuds
Well-known member
I forgot to mention that if there is no exposed metal then there will be no electricity in contact with the water.
That way there's no electrolysis and no corrosion.
My strips do have metal connection points but I could attach my wires then seal them up with silicone or something.
I don't know about the surface of the LED though.
I know there's phosphorus in it but I'm assuming it has a layer of plastic on top ?
That way there's no electrolysis and no corrosion.
My strips do have metal connection points but I could attach my wires then seal them up with silicone or something.
I don't know about the surface of the LED though.
I know there's phosphorus in it but I'm assuming it has a layer of plastic on top ?
PCBuds
Well-known member
I don't know what this guy has in mind.
Probably something more like what Hooka and Reiko mentioned.
But if he were to install sealed strips inside of clear polycarbonate tubes, he could pump water through the tubes, connect flexible tubing to both ends then pump the hot water to a radiator installed outside the greenhouse.
Metal is expensive and corrodes and would probably be more expensive and complicated to install.
Perhaps even heavier too.
If you were to use food-grade stainless steel tubing inside the external heat exchanger as well as an inline reverse osmosis system you could keep the water crystal clear.
We're trying to beam photons through it.
If you were to keep the LED voltage below about 40 volts and mount the drivers above the water lines, it would be safer.
You could install a whole bunch if one-way valves to limit spillage when someone drives a forklift into the water system.
But it is just water, not ethylene glycol like in my car.
You could attach wires to the strips then dip them in clear polyurethane as a last step of manufacturing.
I don't think it would block too much light and it is really durable stuff.
I don't know how good it is at transferring heat but if would be a really thin coating.
Probably something more like what Hooka and Reiko mentioned.
But if he were to install sealed strips inside of clear polycarbonate tubes, he could pump water through the tubes, connect flexible tubing to both ends then pump the hot water to a radiator installed outside the greenhouse.
Metal is expensive and corrodes and would probably be more expensive and complicated to install.
Perhaps even heavier too.
If you were to use food-grade stainless steel tubing inside the external heat exchanger as well as an inline reverse osmosis system you could keep the water crystal clear.
We're trying to beam photons through it.
If you were to keep the LED voltage below about 40 volts and mount the drivers above the water lines, it would be safer.
You could install a whole bunch if one-way valves to limit spillage when someone drives a forklift into the water system.
But it is just water, not ethylene glycol like in my car.
You could attach wires to the strips then dip them in clear polyurethane as a last step of manufacturing.
I don't think it would block too much light and it is really durable stuff.
I don't know how good it is at transferring heat but if would be a really thin coating.
Last edited:
