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Action spectra and RQEs weighted with Cannabis absorptance

This spreadsheet lists the action spectra of various radiation wavebands, as well as their respective relative quantum efficiencies weighted with Cannabis sativa L. absorptance spectrum.

These are the data used in our light source, canopy light (irradiance), and yield efficiency determinations calculated by our spreadsheet "Harvest Irradiance Spectral-System Analyzer" (HISSA).

This thread will be used to post about new versions as we update this file over time. As of v.1.1 it includes only those data required for the v.0.1-alpha release of HISSA. This spreadsheet will be updated in the coming weeks, as will HISSA in turn.

The next post will be used as a changelog, showing changes to the spreadsheet over time. It will be updated with every new vesrion of the spreadsheet.

These data are likely not useful to most growers, unlike HISSA, which is very useful to most growers (indoor and out). We're sharing all these data so we're completely open about what we're doing; we believe strongly in open scientific research, no paywalls. This way it's also easier for other scientists (professional and amateur alike) to help us and to find bugs and other flaws in our work.

The link to the most recent version of the spreadsheet will always be found at the bottom of this post. The file itself is hosted on a website we're part of (more on that later), mostly because this site does not allow uploading of Excel files and we want to have control over the file at our website.

Please let us know if there are changes you'd like to see to this spreadsheet, or if you find bugs, or other issues. Thanks!


v.1.2 (12/31/2014): https://csrg.info/wp-content/uploads/2014/12/Action-spectrums-and-interpolations-v1.3.xlsx
 
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Changelog​




v. 1.3 (12/31/2014):


* Added new action spectrum and aRQEc for that spectrum: DNA photorepair of UV-B photodamage (cucumber)

* Adjusted zoom to 75%, from 100%, on all sheets so they fit more computer monitors without need to zoom-in


v.1.2 (12/23/2014):


- Bug fix update:

* Fixed rounding errors for sheet "McCree; RQE (growth chamb.) 1nm" for wavelength ranges 450 to 461 nm and 601 to 622 nm.

* Fixed rounding error for sheet "McCree; RQE (growth chamb.) 2nm" for wavelength 622 nm.

* Fixed rounding errors for sheet "McCree; RQE (field) 1nm" for wavelength ranges 450 to 457 nm and 601 to 613 nm.



v.1.1 (11/8/2014):


- Bug fix update:

* Fixed spelling of "Outs," it should be "Oats"

* Fixed spelling of "Barely," it should be "Barley"

* Fixed spelling of the genus "Arena," it should be "Avena"

* Fixed spelling of the species "vulgate," it should be "vulgare"

* Fixed misidentification of species by common name, Hordeum vulgare L. is barley, not oats.

* Fixed misidentification of species by common name, Avena sativa L. is oats, not barley.

* Fixed minor formatting issues (thick line separators)

* Fixed missing freeze pane rows for a few sheets

* Fixed typo in cell S92 for sheet titled "McCree; RQE, action & abs." and the associated sheets titled "McCree; RQE (growth chamb.) 1nm" and "McCree; RQE (growth chamb.) 2nm"

* Fixed column width for wavelength nm list for each sheet

* Fixed font size to 12, in some cases it was 11


v.1.0 (11/7/2014):

- The first public release.

- This first release includes only the following determinations (relative quantum efficiencies and action spectra) by 1 nm step size (and 2 nm in some cases). The next version will include 2 nm and 5 nm step sizes and additional action spectra. Action spectra included in this version, including all source data:

* Photosynthesis for indoor C3 plants (mean of 16 species of crop plants)

* Photosynthesis for outdoor and greenhouse C3 plants (mean of 7 species of crop plants)

* Phytochrome photochemical cross-section red absorbing state for phytochrome photo-equilibrium calculation (Rye)

* Phytochrome photochemical cross-section far-red absorbing state for phytochrome photo-equilibrium calculation (Rye)

* UV growth inhibition (Oat)

* PSII photoinhibition (two action spectra and their mean, of A. thaliana)

* Phototropin (stylized typical phototropin-mediated responses)

* UVA-to-cyan radiation mediated stomatal opening (Wheat)

* Cyan-to-yellow radiation mediated stomatal reversal of UVA-to-cyan radiation mediated stomatal opening (Broad bean)

* Mean life span female Cannabis sativa L. var. Colombian absorptance spectrum
 
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Thanks. Glad you like it. Still a lot of more work ahead, but we're getting there.

[EDIT: Well, I guess I posted too soon. I was just notified of a few small bugs, so tomorrow I'll fix them real quick and I'll post about v1.1]
 
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Updated to v1.2. The link is in first post. Bug fixes are listed in the second post.

I was redoing the RQE of Cannabis photosynthesis graphs today and noticed a couple bugs in v1.1.
 
So we made graphs for each of the aRQEc listed in v1.2 of the spreadsheet in the first post. This is a nice way to visualize all these different curves. The following thread will be updated with new graphs as we complete new aRQEc; also, I added lots of links for reading up on each action spectrum/response:

"Various approximate RQE of Cannabis (graphed)"
https://www.icmag.com/ic/showthread.php?t=298468
 
Per your request/offer I will continue my questioning/learning here instead of posting off topic in another related thread. My apologies to the reader if this seems to come out of nowhere.

I will first post that i am out of my element and am struggling to keep up. I apologize in advance for my short coming and beg patience.

My concern is both metrics commonly used to evaluate light (Yield Photon Flux, YPP, and photosynthetic photon flux, PPF) is that both have no concern for the actual energy value of any given photon.

For example a blue photon (450nm) has an energy of 2.8eV.
A red photon (700nm) has an energy of 1.8eV
Red photons have 33% less energy , but are counted as the very same as blue photons.

My point is that if metrics like this are used to drive research/manufacture/marketing/ranking, it seems to suggest that makers of lighting equipment will just focus on exploiting the cheaper energy cost of red photons, and ignoring the value of the more energy expensive blue photons. As well as ignore the value of the broad spectrum of other photons that are also desireable for plant growth.

Honestly, if all people measure are red photons, why make anything else?

Finally I steal a pic from a paper tangentially related.
ZA28Z3F.png


The point of the above pic is practical demonstration that it might be that a blue photon is perhaps worth more than 1 1/3 red ones.
 
Per your request/offer I will continue my questioning/learning here instead of posting off topic in another related thread. My apologies to the reader if this seems to come out of nowhere.

I will first post that i am out of my element and am struggling to keep up. I apologize in advance for my short coming and beg patience.
You're fine, no need to apologize. Glad to help when I'm able.

My concern is both metrics commonly used to evaluate light (Yield Photon Flux, YPP, and photosynthetic photon flux, PPF) is that both have no concern for the actual energy value of any given photon.

For example a blue photon (450nm) has an energy of 2.8eV.
A red photon (700nm) has an energy of 1.8eV
Red photons have 33% less energy , but are counted as the very same as blue photons.
That is because we're only concerned with the energy (quantum radiation) that matters to plants, so that's photon flux. Therefore using photon (micromole) based measurements and comparisons is preferred to other units.

This is the same reason lumens and lux are of little use for growing plants. The same with CRI and kelvins.

My point is that if metrics like this are used to drive research/manufacture/marketing/ranking, it seems to suggest that makers of lighting equipment will just focus on exploiting the cheaper energy cost of red photons, and ignoring the value of the more energy expensive blue photons. As well as ignore the value of the broad spectrum of other photons that are also desireable for plant growth.
I don't think they're mutually exclusive, and they aren't that way in practice, either.

For example, the reason using PPF (umol/m2/s in PAR range) unit is preferred is it doesn't weight wavelength nm, because to do so we need to know what to weight it with in terms of what matters to plants (which is what this thread provides).

Also, when talking about photosynthesis, there's not a lot of difference between effect from blue, green and red ranges, max about 35% difference, but many factors come into play in terms of plants' use of spectral photons for photosynthesis. For example, under strong radiation there's not much difference at all between blue, green and red, and even green can be greater than both blue and red.

So to compare two different lamps you could have the following. Each of these metrics give you a single value for each lamp that can be used to compare to other lamps.

So for example, a CMH lamp (with the same PPF as an HPS lamp) that is rich in blue could have greater "PhotPF" than the HPS (that's rich in yellow/red), but the HPS could have greater YPF than the CMH.


PPF = total quantum radiation emitted in a square meter (umol/m2/s) from 400-700nm:
picture.php





YPF = PPF adjusted with how plants commonly use PAR range radiation for photosynthesis by wavelength. Also, this metric stands on it's own, as "YPF wide," used for wavelength ranges outside of, and including, PAR range:




PhotPF
= PPF adjusted with how plants commonly use blue range radiation for growth. Also, this metric stands on it's own, as "PhotPF wide," used for wavelength ranges outside of, and including, PAR range:


Honestly, if all people measure are red photons, why make anything else?
That's not all that is measured when quantifying PPF, or creating the lamp's SPD. Maybe I don't understand your question.

It's well known that polychromatic based reactions are beneficial to plant growth, and providing full spectrum polychromatic radiation (like 'white light'), optimized for plant growth (such as increased blue range and red range), is best for plant growth (though not always for energy efficiency, hence LEDs).


Finally I steal a pic from a paper tangentially related.
View Image

The point of the above pic is practical demonstration that it might be that a blue photon is perhaps worth more than 1 1/3 red ones.
Please watch this free webinair from LI-COR, the part about plant use of radiation for photosynthesis, and PPF vs YPF, may help explain things better than I'm doing (click the "skip form" link to skip entering personal info):
http://www.licor.com/env/webinars/webinar_4-20-10.html?form=1

The other point I made to you in the other thread was that all of these ways to weight PPF and the lamp's emitted umol/s outside of PAR range are rather inaccurate for a few reasons, so it's better to use PPF as primary unit with these other weighted units as secondary, because the main metric is photosynthesis (so therefore PPF). If any of these aren't clear to you in terms of why they're important, ask and I'll explain further (don't feel like typing a lot of it's not needed):

- Action spectra are created at a low irradiance, normally around 100 to 200 umol/s/nm (in the case of the ubiquitous photosynthetic curve from McCree, it was 150 umol/s/nm)

- Action spectra (at least the majority) are made with monochromatic radiation

- Action spectra are often not created using the species of interest

- Action spectra are often slightly different intraspecies, between different varieties, for example

- Action spectra change with leaf age, and plant age, as well as nutritional status, water stress, etc.

- Action spectra are most often localized, that is, effect studied on single leaves, not 'whole canopy' action spectra (such is the case with the work by McCree)

- Action spectra (at least the majority) use anywhere from 2 nm to 25 nm (or greater) stepsize, which means measurement every 2 nm or every 25 nm (as is the case for data from McCree); the missing wavelength nm value are filled in with math, commonly linear spline interpolation, but in the case of action spectra of photosynthesis (by McCree) and other action spectra, cubic spline interpolation is better
 
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shaggyballs

Active member
Veteran
I was :help: but this was like a life ring........still in the middle of a huge ocean but now I see something beside water.
Thanks for this Beta!

In case anyone missed it, and or you are lost check it out!
free webinair from LI-COR

Beta Test Team; may help explain things better than I'm doing
http://www.licor.com/env/webinars/we...10.html?form=1


Sorry Beta, it did clear things up a little better for me!
But the spoken word always did sink in better.
So rather ...Thanks..not sorry.
Funny I don't like to watch the same movie more than once but I will watch this several times.
Can you say ADD?
Some say they watch movies and see things they missed before.
This is why I suggest to view it more than once.
Lots of good stuff for the head!

Thanks again for that vid Beta.:tiphat:
shag
 
Glad you liked it, I too found it well worth watching.

That gallium arsenide phosphide sensor he spoke about (the one with the biggest errors) is the type used (I believe) by Apgoee and therefore Sun System's "PAR meter."
 

Ranger

Member
This spreadsheet lists the action spectra of various radiation wavebands, as well as their respective relative quantum efficiencies weighted with Cannabis sativa L. absorptance spectrum.

These are the data used in our light source, canopy light (irradiance), and yield efficiency determinations calculated by our spreadsheet "Harvest Irradiance Spectral-System Analyzer" (HISSA).

This thread will be used to post about new versions as we update this file over time. As of v.1.1 it includes only those data required for the v.0.1-alpha release of HISSA. This spreadsheet will be updated in the coming weeks, as will HISSA in turn.

The next post will be used as a changelog, showing changes to the spreadsheet over time. It will be updated with every new vesrion of the spreadsheet.

These data are likely not useful to most growers, unlike HISSA, which is very useful to most growers (indoor and out). We're sharing all these data so we're completely open about what we're doing; we believe strongly in open scientific research, no paywalls. This way it's also easier for other scientists (professional and amateur alike) to help us and to find bugs and other flaws in our work.

The link to the most recent version of the spreadsheet will always be found at the bottom of this post. The file itself is hosted on a website we're part of (more on that later), mostly because this site does not allow uploading of Excel files and we want to have control over the file at our website.

Please let us know if there are changes you'd like to see to this spreadsheet, or if you find bugs, or other issues. Thanks!


v.1.2 (12/31/2014): https://csrg.info/wp-content/uploads/2014/12/Action-spectrums-and-interpolations-v1.3.xlsx

links dead BT, do you have another link for the current spreadsheet?
 

wordsforthewise

New member
This spreadsheet lists the action spectra of various radiation wavebands, as well as their respective relative quantum efficiencies weighted with Cannabis sativa L. absorptance spectrum.

These are the data used in our light source, canopy light (irradiance), and yield efficiency determinations calculated by our spreadsheet "Harvest Irradiance Spectral-System Analyzer" (HISSA).

This thread will be used to post about new versions as we update this file over time. As of v.1.1 it includes only those data required for the v.0.1-alpha release of HISSA. This spreadsheet will be updated in the coming weeks, as will HISSA in turn.

The next post will be used as a changelog, showing changes to the spreadsheet over time. It will be updated with every new vesrion of the spreadsheet.

These data are likely not useful to most growers, unlike HISSA, which is very useful to most growers (indoor and out). We're sharing all these data so we're completely open about what we're doing; we believe strongly in open scientific research, no paywalls. This way it's also easier for other scientists (professional and amateur alike) to help us and to find bugs and other flaws in our work.

The link to the most recent version of the spreadsheet will always be found at the bottom of this post. The file itself is hosted on a website we're part of (more on that later), mostly because this site does not allow uploading of Excel files and we want to have control over the file at our website.

Please let us know if there are changes you'd like to see to this spreadsheet, or if you find bugs, or other issues. Thanks!


v.1.2 (12/31/2014): https://csrg.info/wp-content/uploads/2014/12/Action-spectrums-and-interpolations-v1.3.xlsx
Hey this link is down. Anywhere else I can get this spreadsheet?
 

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