CertifiedRefugee
Active Member
Understood
Gml
- Thread starter cannapotimus
- Start date
cannapotimus
Well-Known Member
I may pick up an apogee meter at some point in the future but until then I’m just reading the plants. I did notice the node spacing tighten up in the plants. The girls are happier than my best runs with how or cobs for what that’s worth as well. They are in a constant state of praying which I usually think of as the first signs of too much light, but the leaves look good and there’s no recent purpling on the stems
CertifiedRefugee
Active Member
@cannapotimus how them babies doing?
cannapotimus
Well-Known Member
They are loving life. I’ve only been running the lights at about 60%, about 18 ish inches from the canopy and the plants are super content with that. I cranked them up to just over 70% in week 3 of flower to see what they can do and the stems on my death bubba purpled up and less than a day. But that particular cut is known to be a little sensitive to light as well. It’s been grown under bulbs for the past 10+ years that I know of so led may be a shock for it.
It was definitely a worthwhile upgrade, I won’t be back home until next weekend, so I’ll snap some pictures then.
CertifiedRefugee
Active Member
cannapotimus
Well-Known Member
It’s Canada Day this weekend too so they may have some good deals if you’re thinking about ordering
CertifiedRefugee
Active Member
thanks on the site now looking no deals yet in the states so next week the 4th of july
cannapotimus
Well-Known Member
Monday is Canada Day so it may not be on there until then. If I recall the 420 deals weren’t advertised either and I didn’t see it until i went to pay, but I’ve smoked a lot of joint since then so I could be remembering wrong.
CertifiedRefugee
Active Member
cannapotimus
Well-Known Member
cannapotimus
Well-Known Member
the girls loves the lights. I’m on week 5 and I definitely notice a little more resin coverage and just better all around bud formation at this stage of flower.
cannapotimus
Well-Known Member
Week seven and the plants are still loving the light. Resin coverage is good but I definitely notice an increase in density, terps and overall growth.
CertifiedRefugee
Active Member
Hell yeah hell yeah
cannapotimus
Well-Known Member
Coming up on 9 weeks, going to be chopping a couple down this weekend and the rest next weekend. All in all I think these lights were money very well spent. I noticed a good increase in density and a bit more terps. Resin coverage still as good or better than my cobs. Overall health of the plants were great. I did get a little foxtailing and had them running at 60% or less for almost the whole time so they are definitely not lacking intensity. I’d definitely recommend these to anyone considering something new.
I checked out the GML site and I think they're a good light. I give kudos to the manufacturer for publishing their PPFD maps and I like the fact that they have a lights with different spectra.
[edit]
Just noticed the comment about getting a PAR meter. I went that route after trying to get good readings from Photone. That was back in 2021 when Photone was still called "Korona" and I couldn't get a reading from my grow light which, back then, was a Kind blurple. After trading emails with the programmer (I've been a software engineer for 30+ years so I have some understanding for how things are working in Photone), I opted for an Apogee.
I'm hard pressed to make an argument for a PAR meter, for most growers. The main reason is that a lux meter (I have the Uni-T) is, for practical purposes, as accurate as a PAR meter. A big reason for a meter is to figure out PPFD is so that you can turn up your light to a certain dimmer and hang height setting to get a certain PPFD value. Let's say your plant is a seedling and you want to get light levels to 300µmol. With an Apogee, you can get a 300µmol reading and it's going to be 5%±. With a lux meter, your lux reading is 5%± and, if you're using the right conversion factor, you're going to be at 300µmol as well.
That's all well and good but it doesn't how much light is coming from the light fixture. What really matters is now much light your plants can use and the only way to understand that is to see how your plants are reacting to the light that they're getting. If you get your seedlings to 300 and they're doing fine, you can turn up the dimmer and the PPFD will be 400µmol. At that point, if your seedlings can't tolerate that level of light (and they probably won't) they'll let you know by curling up the edges of their leaves or, perhaps, turning the leaves vertical like the way a Venetian blind is rotated.
The fact that your leaves were praying is a good sign and I agree with you 100% that they were probably right on cusp of having too much light. That tells us that the plants were, probably, right at their light saturation point. That means they're getting the maximum amount of light they can handle and that a means they're growing at their maximum rate. That's exactly what's needed to maximize yield.
My experience has been that plants only pray at certain times in their lifecycle. I've got no data on that-that's just my recollection.
If your budget won't take a hit getting a PAR meter, I have no complaints about the Apogee. I would get the sensor that measures ePAR, which is a range slightly larger than standard PAR because lights are being manufactured with diodes that generate photons <400 and >700. I bought a case for my Apogee and, with a wand, you can get readings with the tent doors closed. Another meter that seems to be worthwhile is the Spot On. I don't have any experience with it but the manufacturer appears to be reputable and it's available on Amazon or through Migro. There are inexpensive PAR meters on Amazon. I would recommend a lux meter rather than an inexpensive PAR meter but I don't base that on first hand knowledge.
For a mere $32, you can get a Uni-T lux meter and it will do a good job for you. I've attached a document I've written about converting lux to PPFD. The trick is to get the right conversion factor and I've listed out about a dozen lights and their corresponding factors. All in all, 0.015 will get you very close to the actually PPFD value but it's best to try to match as closely as possible.
Congrats on the grow, BTW. Very nice looking plants!
[edit]
Just noticed the comment about getting a PAR meter. I went that route after trying to get good readings from Photone. That was back in 2021 when Photone was still called "Korona" and I couldn't get a reading from my grow light which, back then, was a Kind blurple. After trading emails with the programmer (I've been a software engineer for 30+ years so I have some understanding for how things are working in Photone), I opted for an Apogee.
I'm hard pressed to make an argument for a PAR meter, for most growers. The main reason is that a lux meter (I have the Uni-T) is, for practical purposes, as accurate as a PAR meter. A big reason for a meter is to figure out PPFD is so that you can turn up your light to a certain dimmer and hang height setting to get a certain PPFD value. Let's say your plant is a seedling and you want to get light levels to 300µmol. With an Apogee, you can get a 300µmol reading and it's going to be 5%±. With a lux meter, your lux reading is 5%± and, if you're using the right conversion factor, you're going to be at 300µmol as well.
That's all well and good but it doesn't how much light is coming from the light fixture. What really matters is now much light your plants can use and the only way to understand that is to see how your plants are reacting to the light that they're getting. If you get your seedlings to 300 and they're doing fine, you can turn up the dimmer and the PPFD will be 400µmol. At that point, if your seedlings can't tolerate that level of light (and they probably won't) they'll let you know by curling up the edges of their leaves or, perhaps, turning the leaves vertical like the way a Venetian blind is rotated.
The fact that your leaves were praying is a good sign and I agree with you 100% that they were probably right on cusp of having too much light. That tells us that the plants were, probably, right at their light saturation point. That means they're getting the maximum amount of light they can handle and that a means they're growing at their maximum rate. That's exactly what's needed to maximize yield.
My experience has been that plants only pray at certain times in their lifecycle. I've got no data on that-that's just my recollection.
If your budget won't take a hit getting a PAR meter, I have no complaints about the Apogee. I would get the sensor that measures ePAR, which is a range slightly larger than standard PAR because lights are being manufactured with diodes that generate photons <400 and >700. I bought a case for my Apogee and, with a wand, you can get readings with the tent doors closed. Another meter that seems to be worthwhile is the Spot On. I don't have any experience with it but the manufacturer appears to be reputable and it's available on Amazon or through Migro. There are inexpensive PAR meters on Amazon. I would recommend a lux meter rather than an inexpensive PAR meter but I don't base that on first hand knowledge.
For a mere $32, you can get a Uni-T lux meter and it will do a good job for you. I've attached a document I've written about converting lux to PPFD. The trick is to get the right conversion factor and I've listed out about a dozen lights and their corresponding factors. All in all, 0.015 will get you very close to the actually PPFD value but it's best to try to match as closely as possible.
Congrats on the grow, BTW. Very nice looking plants!
Last edited:
cannapotimus
Well-Known Member
Thanks man. I’ll look into that.
cannapotimus
Well-Known Member
First run with the lights is finished. Everything is all hung up to dry. Very happy with the new lights. This run could have been better but the summer heat and humidity were both higher than I’d like. 
CertifiedRefugee
Active Member
Awesome
cannapotimus
Well-Known Member
No worries, feel free to join in here buddy. I just made this thread so people can find info and reviews on grandmaster lights since I couldn’t find anything else on here.