light science, metrics

MImedpatient

Well-known member
I wanted to link a few videos here to get people more familiar with the why's and how's of light, and why to choose the light source you choose. RileyQuin and Cannalicious inspired me to share this w/ a conversation from another thread for the ease of all here

I am just a guy, I am not advertising products to you. the people in some of these videos are, and I am sorry about that. but I chose to share them as they are very informative videos, and the dr mj coco and albo pepper videos are very helpful for explaining things that I have difficulty articulating.
Migro puts the new lights he reviews on the list he shows in that video.
 
Sunlight is best. For a myriad of reasons. One being that lights falls off at the inverse square of the distance from the source. Take any light meter and test this out. Outside, measure the light 10 feet off the ground and at ground level. The sunlight is constant. This is because 93 million miles +/- 10 ft is pretty much the same as 93 million miles. Now go inside and measure any electric light 1 foot from the source and then 10 feet from it. At 10 feet, your meter will read 1/100th the light as it will from 1 foot. This is because 1/(10*10) = 1/100. 10*10 is the inverse square of the distance 10 feet from the source. That makes all of these lights very limited in the canopy that they can support. As in lower leaves do not get any light. Then there is the light spectrum, and initial cost, efficiency, fixtures, space, and electric cost. Sunlight has the best spectrum. It is also free. Hard to beat that. Hence I grow in greenhouse outside.

I am, among other things, a degrees electrical engineer. I studied light as much as I did electricity at university and as an engineer. A lot of this stuff is just advertising BS IMO. I have yet to see 'the truth' from any of these types of posts. Most (if not all) are just hype and sales pitches. I still use old school HID HPS ballasts and newer wider spectrum MH bulbs in them. Cheap as chips to buy, more expensive to run. Low up front costs though. Good results. I have yet to see any "better" LED lights. Flat plane arrays of LEDs are dumb, for the reason that indoor bulbs are dumb. They are all point or plane source and limited by the same inverse square of the distance physics law that I point out above. I only use the lights starting seedlings indoors in the late winter and finishing seed runs indoors the fall if the outdoor weather turns here early.
 
...Sunlight has the best spectrum. It is also free. Hard to beat that...
...I still use old school HID HPS ballasts and newer wider spectrum MH bulbs in them...

Seems this topic comes up every so often. Of course, there are advantages and disadvantages to both. Each fills a niche. For instance, I heat my house with HID, which is an economic benefit. For me, the ROI isn't yet there for LED. I just bot 2 backup quantum 600w digital ballasts for $212. iPower is selling a complete 600w HID system that includes ballast, fixture, timer, ratchet system, both hps and mh bulbs for less than $200. Multiply that by 2 makes $400. You're in business covering 8 square. Light penetration? Throw a chicom 1200w LED to the side for $130. Total investment $530 for 8 square. Easy to amortize. Compare 2 HLG 650 at $2000 for just the boards, doesn't include heating source that may be needed. What to do with that $1400 savings? A new jap glassed 6-30x will fit nicely on the .308 lol. I'm gonna wait a little longer; with LED tech evolving every two years, it currently is an expensive proposition. Something about the future value of money (FV) and the idiom "If it ain't broke, don't fix it." Of course, my two cents and coming from a guy who still runs an old HP 12-C and tubes in my Fender Deluxe Reverb lol.

🤙Mu
 
musashi, coming from a guy who still runs......tubes in my Fender Deluxe Reverb lol.

Comparing a tube amp and a solid state amp is like comparing sunshine to artificial indoor light. I'll take the tube amp and sunshine every time!

Longball
 
ive got no relation to the other dde posting light shit,
Sunlight is best. For a myriad of reasons. One being that lights falls off at the inverse square of the distance from the source. Take any light meter and test this out. Outside, measure the light 10 feet off the ground and at ground level. The sunlight is constant. This is because 93 million miles +/- 10 ft is pretty much the same as 93 million miles. Now go inside and measure any electric light 1 foot from the source and then 10 feet from it. At 10 feet, your meter will read 1/100th the light as it will from 1 foot. This is because 1/(10*10) = 1/100. 10*10 is the inverse square of the distance 10 feet from the source. That makes all of these lights very limited in the canopy that they can support. As in lower leaves do not get any light. Then there is the light spectrum, and initial cost, efficiency, fixtures, space, and electric cost. Sunlight has the best spectrum. It is also free. Hard to beat that. Hence I grow in greenhouse outside.

I am, among other things, a degrees electrical engineer. I studied light as much as I did electricity at university and as an engineer. A lot of this stuff is just advertising BS IMO. I have yet to see 'the truth' from any of these types of posts. Most (if not all) are just hype and sales pitches. I still use old school HID HPS ballasts and newer wider spectrum MH bulbs in them. Cheap as chips to buy, more expensive to run. Low up front costs though. Good results. I have yet to see any "better" LED lights. Flat plane arrays of LEDs are dumb, for the reason that indoor bulbs are dumb. They are all point or plane source and limited by the same inverse square of the distance physics law that I point out above. I only use the lights starting seedlings indoors in the late winter and finishing seed runs indoors the fall if the outdoor weather turns here early.
Seems this topic comes up every so often. Of course, there are advantages and disadvantages to both. Each fills a niche. For instance, I heat my house with HID, which is an economic benefit. For me, the ROI isn't yet there for LED. I just bot 2 backup quantum 600w digital ballasts for $212. iPower is selling a complete 600w HID system that includes ballast, fixture, timer, ratchet system, both hps and mh bulbs for less than $200. Multiply that by 2 makes $400. You're in business covering 8 square. Light penetration? Throw a chicom 1200w LED to the side for $130. Total investment $530 for 8 square. Easy to amortize. Compare 2 HLG 650 at $2000 for just the boards, doesn't include heating source that may be needed. What to do with that $1400 savings? A new jap glassed 6-30x will fit nicely on the .308 lol. I'm gonna wait a little longer; with LED tech evolving every two years, it currently is an expensive proposition. Something about the future value of money (FV) and the idiom "If it ain't broke, don't fix it." Of course, my two cents and coming from a guy who still runs an old HP 12-C and tubes in my Fender Deluxe Reverb lol.

🤙Mu
musashi, coming from a guy who still runs......tubes in my Fender Deluxe Reverb lol.

Comparing a tube amp and a solid state amp is like comparing sunshine to artificial indoor light. I'll take the tube amp and sunshine every time!

Longball
I get new glasses in 2 weeks as it will be awhile for them to ship, but I am excited to talk to yall about the difference between lights and the metrics we choose. I play bass and guitar poorly, and IMO solid state amps w/ tube pre amp pedals are pretty badass. especially for lugging around to friends houses to play. Gotten more than a few compliments on my gear when someone else plugs in.
 
I’m no technical expert and well known in which brands are best, as they evolve within years now. But I have tried led and have a heated watertank. This brings humidity up and with hps on this humidity drops significant but not with led.

I also don’t find it worth the investment given changing a hps bulb costs only 30 euro. I did not invest much in led so don’t take my word for it anyway. I find it great for growing and others may get great flowering results. But I prefer hps and specially during winter time.

There are brands saying 300 watt led equals 600 watt hps, I truly wonder it is equal to a 600 watt hps on 1,2 square meter. I think you need more LED to fully illuminate the 1,2 square meter which will add up to more then 1x 300 wattLED.
This may be too pre judgmental.
 
Aloha & This is some good research on modern vegetables. I have always loved the research from the University of Florida and their good Doctor from the the land down under.
 
For smaller indoor grows the 50-400w leds are a great solution. Im currently running 2 kingbright quantum boards around 220w draw together. Produced some really fine bud so far.
I just dont have the ability to exaust the heat from a hps setup or anything past 300watts. So i wouldnt be growing if these were not a thing. My experience is positive so far. Having never used an hps or cmh i couldnt say how it compares.
Peace all.
 
My 300W Cob led setup yielded me 570g solid nuggets of SSH that makes 1,9g/W... so if you ask me is it equal to a 600W HPS ? to me it is. Ive never done much better than 1,1g/w for a HPS light setup with the same amount of flowering weeks.
I believe that, but it don’t believe you achieved this under 100 euro. 600 watt hps system is little over 100 euro. 300 watt cob led would take 5 to 6 (56 watt) cobs costing each 120 euro. When broken, does one replace the led or does the entire system needs to be replaced?

This also may be too pre judgmental. I have been checking those new systems yesterday with dimmers, sunsets and sunrises. Costs a lot of money but they promise a life span of 100000 hours. That is 22 years leaving them on for 12h a day. It was a Mars Hydro FC 6500 Led Grow Light Full Spectrum Samsung LM301B Osram Diodes Inventronics Driver Hydroponic

I may want to reconsider my position on them.

Edit: it was correct math and I editted it for nothing.
 
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My 300W Cob led setup yielded me 570g solid nuggets of SSH that makes 1,9g/W... so if you ask me is it equal to a 600W HPS ? to me it is. Ive never done much better than 1,1g/w for a HPS light setup with the same amount of flowering weeks.

my best havest indoor was 480g with a 600hps

i got beetween 350 and 400 g with it in general

you are very good if you have this result
 
Nope not under 100 euro, but hey the Led cobs im already running them more then 6years now every day! My worst score with this setup was still 0,9g/W thats something that still is a challenge under a HPS setup. To me its also the savings on the electric bill, its saves me about 400bucks a year running the 300w led compared to 600w hps. And the lower electric usage is also helping me not being found by the law.

if you can build yourself, a single COB with heatsink and driver would cost a lot less then that 120 bucks. I can build them for about 50 bucks each, with own driver it will put out 50W. The total 300W COB setup would cost me about 240 euros to build myself now a days. If going for led strips it can be even cheaper to build. Im talking with the highest quality leds i can buy as consumer Samsung, Cree, Citizens. And thats where most people get screwed over, there is so much el cheapo leds on the market performming below a HPS its actually hard to see the best tree in the woods.

watch out with buying lamps of the brand MARS HYDRO they do use the better quality leds now a days but still providing a terrible driver with their setups and their consumer service is really shitty aswel.


thanks @quinxstar im not feeling like im very good at all :giggle: your scores are not bad brother! I think if you would run a tight setup with clones from 1 mom you can reach 1g/w also in your setup!
 
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lets see if the superglue holds my glasses together this time!
my best havest indoor was 480g with a 600hps

i got beetween 350 and 400 g with it in general

you are very good if you have this result

that is pretty badass! i pulled 1.5 pounds of Green lotus w/ 4 plants in a 4 x 4 x5 homemade grow box under a 600w hortilux super hps. but that's a heavy yeilding green crack hybrid so it literally was the plant, not me. I normally pulled just shy of a pound of normal yeilding indica and hybrid plants out of that space. my best was 3 pounds per 1k input w/ 4:1 ratio of HPS to blurple leds, growing big ole hashplant og hybrids in a room.

Nope not under 100 euro, but hey the Led cobs im already running them more then 6years now every day! My worst score with this setup was still 0,9g/W thats something that still is a challenge under a HPS setup. To me its also the savings
watch out with buying lamps of the brand MARS HYDRO they do use the better quality leds now a days but still providing a terrible driver with their setups and their consumer service is really shitty aswel.


thanks @quinxstar im not feeling like im very good at all :giggle: your scores are not bad brother! I think if you would run a tight setup with clones from 1 mom you can reach 1g/w also in your setup!
impressive yields!, my friend did plug one of my mars hydro 600w classics in at his house a few years ago and the diodes melted upon plugin, supposedly they are alot better now w. the full spectrum white w/ far red fixtures than they used to be.
for the DIY people in North America, Pacific light concepts does good work at providing affordable equippment, and the owner does youtube videos about DIY. so does GrowMau5. I fully recomend people do DIY if they love it or find a as local to them as possible company to get the full spectrum white w/ far red spectrum leds from. this stuff is the efficient future base spectrum we will all be using IMO

Seems this topic comes up every so often.

🤙Mu

I agree, if I was going for quickest startup and ROI I too would choose to snag an afforable HPS/MH setup. I built my grow and and a few others off of craigslist purchases of used HID gear. a 1k ballast, and sealed 8 inch ducted hood is 100 dollars together used, a raptor hood(big ole hood) is 75-125 dollars. bulbs at my local hydro store can be bought at 6 bulbs for 100 dollars. if you need to get rolling ASAP its literally the best way to start if you don't have a big pile of cash to help you get started. I do not like heating my house up in the summer, and I do not need to heat my house up to 80 degrees in the winter w/ MH and HPS. I disagree w/ your assesment of it not being worth the investment.

I contacted my local hydro stores that are distributors for the larger brands of LED. growers choice, hlg, gavita, mars, viparspectra, mars hydro, I then contacted each manufacturer w/ my quoted price, and asked if they could beat the store price. the stores offered me 853 each on the 650r's hlg through medgrower1(youtuber who is a distributor) for 800 each. I DIDNT EVEN HAGGLE.

I buy the cheap 6/100 dollar hps bulbs. they only last 3 months before they drop in output. thats 250ish a year on bulbs saved. these lights can run for minimum of 3 years, and likely will last 5 or 6 as people are just now switching from the old models of led to the new ones. If I have my lights for 5 years, I will have saved 1250 dollars on bulbs. then, considering that my space is now covered better, for 37% less energy(before any other fans or AC are factored in). electricity costs 15 cents per KWH here on average a 1k hps costs about 54 dollars a month to run. a 650r costs 34.2 dollars per month to run, that is 19.80 saved per fixture per month, in flower. this is a savings of 950.40 a year for me. if my lights last for 5 years, this is a savings of 4752 dollars w/ the bulb savings it is 5002 saved; add 33% more for veg lighting on all those numbers. Now, consider I was able to also take down a 200w exhaust fan(for the air cooled lights), my AC is now happily keeping the flower room between 70 and 73F instead of struggling to keep it around 75, MY room intake and exhausts for the room itself are now off for 45 minutes at a time and on for 15 instead of 15 on 15 off. my too large of space for single ended hps is now covered more properly, meaning my cost savings are also increasing my yeild. I also purchased some for my veg room, and they are 10/10 leagues above the cheap 1k SE metal halide bulbs in terms of plant response.

I have this many lights in my room. and yes, my eyes feel like captain picard does at the end of that scene even w/ sunglasses and a hat after working under these beasts.

Also, Nice amp! I have an 80s peavey solid state keyboard/bass amp w one of the Behringer tube pedals to drive it a little harder and the Sansamp clone for bass, although the amp is crystal clear and thumps all on it's own.

I may want to reconsider my position on them.

bar style is for low ceilings/stacking vertically w/ shelves/chambers in a tall ass warehouse, board style = hps type shoots light down through canopy replacement whe we are talking about these white w/ far red full spectrum leds.
Take that into account when you make your choice on bar vs board.

If you don't want to make the switch that is on you. I am glad you are not being judgmental as this may very well be the future base type of lighting we all use, and then add HPS or CMH or COB LED and get to alter spectrums to what we want for our plants. my one friend is deciding between vipar spectra and mars hydro's 200-300w lights for a 3x3.

my friend who grows very inefficiently(does not utilize his full wattage, complains about costs) is considering a pair the hlg 225 and hlg 100v2 for flower and veg respectively, as this covers the footprint of his flood tables, 3x3.

My other friend refuses to hear anything about any brand but gavita.

the friend who is deciding between the vipar and mars for a 3x3, pulled 5 ounces out of a 2x2 w/ the 125w vipar spectra 12 band led, or the RBG 3 switch, I forget which) with a mac one caps cut I gave him.

If the brand slaps together the samsung and or osram diodes, even the epistars, runs the meanwell or other quality brand drivers is all that really matters.

four part series with research and evaluations

Thanks for sharing! I do feel that when heat is not needed, that these white w/ far red full spectrum leds will be very helpful for supplemental greenhouse lighting in cloudy or northern climates! fall and spring when heat isnt as needed as in winter comes to mind as the proper scenario.

Then there is the light spectrum, and initial cost, efficiency, fixtures, space, and electric cost. Sunlight has the best spectrum. It is also free. Hard to beat that. Hence I grow in greenhouse outside.

electrical engineer. I studied light as much as I did electricity at university and as an engineer. A lot of this stuff is just advertising BS IMO. I h only use the lights starting seedlings indoors in the late winter and finishing seed runs indoors the fall if the outdoor weather turns here early.

I agree the sun is the best, but not all of us are lucky to be able to happily grow outdoor even with legalization. I have to deal with smell ordinances. Indoor till I can pull permits for a greenhouse. LED's for light supplementation when heat is not needed, HPS for when it is llater into the fall, or late in winter/early spring while snow is still a threat.

You may enjoy Dr Bugbee's video's that are more like classroom lectures than his more sales pitch type videos. I am sad most of the useful grow light information is in videos trying to sell us products, as I only express brand loyalty based on quality of work and I cant personally validate what's good and what's trash in 99% of video's I want to link, and as I own the HLG lights I don't want to link the videos reviewing them as I don't want to seem like an advertiser when I am not. I just want all of us to be on the same page as unlike you, most of us didn't learn about this at college. I would love for you to assist in parsing out the advertising bullshit and get us to the information in the videos if you have the time.

You may very much like the new spectrum of LED that came out this past year, I was astounded when a spider farmer sf 4000 replaced a 1k Single ended metal halide for veg. I was thoroughly impressed when the 650r's did more than replace 1k SE hps. the spectrum is more similar to CMH, CHPS, or general full spectrum hps/mh conversion lamps, and the plants love it, they penetrate the same as an HPS/MH its meant to replace

for you, and others who use lights like you, including myself, as that's how I start my vegetable garden now so I can have tomatoes, peppers, and cucumbers before the neighbors have even bought baby plants, using MH or HPS for a couple months is far from the worst thing, and it is not worth buying an expensive led for you, and others in the same situation. it would take like 20 years to make the savings pay for the light.
 
Indeed. Young plants do not need as much light to get started. I like the new MH conversion bulbs for convenience using my old HPS ballasts and reflectors. I also really like the wider spectrum over older MH bulbs. And the price. Less of an impact using the wider spectrum lights when moving young plants outdoors as they will already have some UV exposure. I have yet to use these MH conversion lights finishing plants in the fall. HPS still puts out the most light of any HID bulbs, but I do not like the red shifted light in them. Sour taste from them? Vs. sweet from MH and sun? I prefer blue shifted spectrum light. I will likely never grow indoors full time as I have acreage here and 5 greenhouses outdoors. I grow more than I can smoke as it is, so no point in growing over winter indoors here. LEDs are certainly more efficient, but... the up front cost is still high. I have yet to be sold on them. If I was starting out fresh I would probably go that route. But switching over does not make much sense. Yet.
 
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Indeed. Young plants do not need as much light to get started. I like the new MH conversion bulbs for convenience using my old HPS ballasts and reflectors. I also really like the wider spectrum over older MH bulbs. And the price. Less of an impact using the wider spectrum lights when moving young plants outdoors as they will already have some UV exposure. I have yet to use these MH conversion lights finishing plants in the fall. HPS still puts out the most light of any HID bulbs, but I do not like the red shifted light in them. Sour taste from them? Vs. sweet from MH and sun? I prefer blue shifted spectrum light. I will likely never grow indoors full time as I have acreage here and 5 greenhouses outdoors. I grow more than I can smoke as it is, so no point in growing over winter indoors here. LEDs are certainly more efficient, but... the up front cost is still high. I have yet to be sold on them. If I was starting out fresh I would probably go that route. But switching over does not make much sense. Yet.
I have flowered plants under MH and HPS both separate and mixed spectrum. What do you mean sweet vs sour taste? because I never noticed a difference like that between 2 identical clones where the only differecne was hps or mh.
My plants prefer to flower in a 3:1 ratio of hps to MH for maximum bulk. its why I was so impressed w/ this led spectrum. I dont have to move plants around everyday to maxmize the spectrum they get, it sounds worse than it is becasue it was just a clockwise quadrant rotation, but tedium is tedium.
. I wish my patients didn't burn down blunts like they were cigarettes so I could be in that boat. I would live to have a surplus.
 
superglue did not hold for long, I cant respond until I can fix it better or my new glasses arrive, I don not like super glue flkes in my eyes.
2 new videos popped up, one by Dr Bruce Bugbee and AlboPepper, in my recomendeds on youtube.
warning, this video is a partial advertising for one of his meters. it also gives a very decent overview of UV.
I am about to listen to this one, I love Albo, He speaks plainly about the products he is pimping. And I feel he does fair comparisons.
edit
He claims this is an unpaid review!!!!
edit
So m,any slides!
edit
damn, he tears into some brands
 
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I have flowered plants under MH and HPS both separate and mixed spectrum. What do you mean sweet vs sour taste? because I never noticed a difference like that between 2 identical clones where the only differecne was hps or mh.
My plants prefer to flower in a 3:1 ratio of hps to MH for maximum bulk. its why I was so impressed w/ this led spectrum. I dont have to move plants around everyday to maxmize the spectrum they get, it sounds worse than it is becasue it was just a clockwise quadrant rotation, but tedium is tedium.
. I wish my patients didn't burn down blunts like they were cigarettes so I could be in that boat. I would live to have a surplus.

Well, I have not seen that much of a difference in taste finishing plants under lights, sweet or sour, but many growers have noted that phenomena. More sour under HPS, and sweeter under MH.

No issues with amounts of weed grown here, as we are only limited here in number of plants growing, not size. I can grow up to 4 + 6 + 12 = 22 plants legally the size of my garage if I want to. They just have to be out of sight with the unaided eye from the highway. I can grow indoors or out, or in GH. Only 10 plants can be in flower at any one time though. I make hash with most of my dried colas. Sifted hash tumbled in a freezer works best. Yummy yellow hashish powder. I freeze that and it should last virtually forever. Well, as long as I will be around anyway. I give more weed away here than I smoke. Many of us do that here. This year I grew more hemp and it was not much in quality to smoke, so some friends buired me with their really good weed. It is also so cheap here to buy. If I want to try a new or different strain, it is cheap and discounted even more and not taxed with a grow card here. There is still a huge weed oversupply issue in Oregon.

Were that I had this stuff in these amounts when I was 18 on the Monterey Peninsula and SF Bay Area? I would have been a GOD. I had some of my landrace seed collection then, and lots of bag weed seed to choose from, but no way to grow this much weed. Or my current knowledge of how to grow it. Well, one year I did grow a huge lot in Carmel Valley in 1973, but the 100 or so plants were found by the ranch foreman when they were 4 feet tall in August, and he pulled them all up and burned them. We were not implicated, but we suffered the loss. About 12 years ago in Southern Oregon I grew 26 pounds of dried finished bud. That was the record for me. I gave a lot of it away, and my ex smoked it up like a chimney. Which is why I grew that much that year. The year before I grew a pound or so, and she smoked it ALL. So I decided to grow more than she could possibly smoke. Then she complained that it was not strong enough? *cough* I grow lighter strains as a rule... Lebanese, Mexican, Durban, etc. Not couch OG Kush style weed. She would love the hash I make now though. Sigh. I have not heard from her in some years now. *shrug*
 
I have only grown under CMH but one thing I noticed is the meatiness of the buds compared to my buddies grows and shops. The buds aren’t wispy. They don’t crumble into nothing as much as the LED grown dainty ones of my buddies. Even if it is a fluffier strain. The stems are sturdy. I also only use organic dirt no chem. It might be why. I’m not sure what they use. Could be the dirt. Could be the ferts. I think it is the lights contributing greatly in my very limited experience.
 
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