have a red spec board with red and infar-red light and deep red+ blue spectrum + uv if needed (in flower only) far red increase light pentration -- very good info from memebrs on this subject, much to digest. Then again genetics/strains might be a guide line for use of ? anyway happy with QB's
I'd like to talk about using far red during flowering.
- Thread starter Photon Pharms
- Start date
the study of light and its application to cannabis has always been one of the most fascinating aspects of growing for me.
i have never grown with a pre-manufactured led fixture and it occurred to me after my post above that maybe a lot of the manufactured ones were totally lacking in far-red.
maybe that's why a lot of manufacturers are touting far-red on their newer lights.
i have been using screw-in household leds and i think they have some significant small amount of far-red and that my array is not lacking.
so i may not see the difference in effect that you folks with manufactured lights do.
my 120 bulb 1680 watt array for flower is composed of 60 5000k bulbs and 60 2700k bulbs.
there is palpable heat being projected straight down and it can be felt on the back of your hand strongly at about 6".
i have a fan above the light pulling air up counter to this heat yet it is still there.
although i don't have a far-red meter i can feel it.
i veg under the 5000k lights alone and get very tight nodal spacing before flower.
manipulation of light spectrum helps me keep my plants short and compact but still yield well.
the idea that far-red gives significant foliage penetration is erroneous.
far-red does penetrate leaves whereas shorter wavelengths do not as much.
this penetration is more for morphology than photosynthesis in cannabis.
on the adaxial surfaces of the fan leaves, there are randomly distributed cells that sense the quality of light between 660-730 nm.
when these cells become occluded they signal the stem section above the fan leaf to elongate.
with my par meter on top of the canopy and a reading of about 1500 umols at the top surface of a single leaf i will get less than 200 umols immediately below that single leaf.
that means virtually no photosynthetic use of far-red as that is below the compensation point.
so i guess i a little far-red is probably necessary for good flower growth.
the intensity is more important than the correct spectrum but both is better.
i have never grown with a pre-manufactured led fixture and it occurred to me after my post above that maybe a lot of the manufactured ones were totally lacking in far-red.
maybe that's why a lot of manufacturers are touting far-red on their newer lights.
i have been using screw-in household leds and i think they have some significant small amount of far-red and that my array is not lacking.
so i may not see the difference in effect that you folks with manufactured lights do.
my 120 bulb 1680 watt array for flower is composed of 60 5000k bulbs and 60 2700k bulbs.
there is palpable heat being projected straight down and it can be felt on the back of your hand strongly at about 6".
i have a fan above the light pulling air up counter to this heat yet it is still there.
although i don't have a far-red meter i can feel it.
i veg under the 5000k lights alone and get very tight nodal spacing before flower.
manipulation of light spectrum helps me keep my plants short and compact but still yield well.
the idea that far-red gives significant foliage penetration is erroneous.
far-red does penetrate leaves whereas shorter wavelengths do not as much.
this penetration is more for morphology than photosynthesis in cannabis.
on the adaxial surfaces of the fan leaves, there are randomly distributed cells that sense the quality of light between 660-730 nm.
when these cells become occluded they signal the stem section above the fan leaf to elongate.
with my par meter on top of the canopy and a reading of about 1500 umols at the top surface of a single leaf i will get less than 200 umols immediately below that single leaf.
that means virtually no photosynthetic use of far-red as that is below the compensation point.
so i guess i a little far-red is probably necessary for good flower growth.
the intensity is more important than the correct spectrum but both is better.
Photon Pharms
In Bloom
Check out Scynce Led.
high, photon pharms! nice to meet you! please don't think this is any kind of an attack on anyone or their product. it is just a superficial analysis of claims.
so i did check out scynce leds and the first thing i found was this:
this is a youtube video explaining why you can't accurately measure their light with a par meter.
notice in this video that he is using an apogee meter.
he is trying to say that the meter doesn't adequately read total light from combined angles at any given point below the light.
now go to this:
this paper clearly states that apogee meters read total light hitting it from any direction.
not perfectly but so good that it looks as if the guy in the video is being intentionally misleading.
you should be able to take an apogee meter and place it flat at all the points on a grid and then average that delivery over the entire surface to get an accurate idea of what the light is capable of.
a grow light manufacturer should know better than this.
the light may be the best light in the fucking world but if so why do they feel they need to obfuscate?
so i did check out scynce leds and the first thing i found was this:
this is a youtube video explaining why you can't accurately measure their light with a par meter.
notice in this video that he is using an apogee meter.
he is trying to say that the meter doesn't adequately read total light from combined angles at any given point below the light.
now go to this:
this paper clearly states that apogee meters read total light hitting it from any direction.
not perfectly but so good that it looks as if the guy in the video is being intentionally misleading.
you should be able to take an apogee meter and place it flat at all the points on a grid and then average that delivery over the entire surface to get an accurate idea of what the light is capable of.
a grow light manufacturer should know better than this.
the light may be the best light in the fucking world but if so why do they feel they need to obfuscate?
My take on such a claim would be for the following reasoning.
I didn't watch that video, but I have watched other videos, and done research on the subject. The apogee can only register wavelengths 389-692, so anything above or below those wavelengths doesn't register in its readings.
So the 730 reds don't account in its par readings. So I could see where someone would/could be making claims like that, that apogee sensor isn't reading the lights full output. Diff angle stuff, not so much.
But again, I didn't watch the vid to hear his claims. Lol.
hey buddy!
yes, but even accounting for a 5% far-red his readings are not that great.
not picking on scynce but in general, among most led grow light manufacturers i'm seeing a trend towards dishonesty.
i don't know about you but personally, i'm shocked and dismayed! not really but we (the consumers and growers) should be getting the real deal holyfield for our hardly earned money.
in the scynce video he states that this light produces 1000 umols of flow at 24" yet we didn't see anything like that in the video.
but assuming it does at some point does it do it evenly across the entire canopy?
the point is that they have not adequately quantified the total output of their light both in the normal par range or far-red.
the older i get the more hung up i am on trustworthiness.
yes, but even accounting for a 5% far-red his readings are not that great.
not picking on scynce but in general, among most led grow light manufacturers i'm seeing a trend towards dishonesty.
i don't know about you but personally, i'm shocked and dismayed! not really but we (the consumers and growers) should be getting the real deal holyfield for our hardly earned money.
in the scynce video he states that this light produces 1000 umols of flow at 24" yet we didn't see anything like that in the video.
but assuming it does at some point does it do it evenly across the entire canopy?
the point is that they have not adequately quantified the total output of their light both in the normal par range or far-red.
the older i get the more hung up i am on trustworthiness.
