Lately I've been pouring through spectrum graphs, trying to decide (for like the third time) what I want my T5 set up to look like. Looking at these graphs, I feel like there is an inconsistency regarding the Red Sun graph and I wonder what it means.
The Red Sun is billed as a 633 nm light, but that's not what their spectrum graph makes it look like, as you can clearly see when you blow it up a little and throw in some more unit lines:
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Has this been discussed? I don't remember it coming up in the thread, previously.
I see two possible conclusions that can be drawn from this:
1. While the Red Sun has some light output at around 633 nm, the bulk of it is actually closer to 615 nm, which, incidentally, is yellow/orange on any other spectrum graph. If this were the case, the bulb is not helping people as much as (or at least the way that) they think it is. Though, if the contention is Red Suns do substantially help growing even if their spectrum is as represented in this graph, then light in that range has been underestimated (the supposedly unfortunate yellow spike on the 75.25 is right in this range, for instance).
or
2. The Red Sun peeks at 633nm and the graph is off. This does not seem at all unlikely to me, but I want this graph to be accurate. If it isn't, how can we have faith in any of the spectrum graphs? Certainly they're not random, but how should the extent of their (in?)accuracy influence our judgement of different bulbs, especially when comparing between brands (which may have differences in the quality of their graphs). Do we judge some bulbs too harshly, considering the bulb we hold it up against has a questionable spectrum graph to begin with? (I don't mean the Red Sun specifically here, probably the Fiji is the best example of this at this point)
So what is everyone's take on this? How do you feel about your Red Sun and its graph? Is there another possible conclusion?
Thinking about this has brought me back to one of Prof's first graphs, that of the photosynthetically active spectrum:
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This reminds me that we're not necessarily looking to dial in on a few specific wavelengths at the exclusion of all others (which is actually what most appeals to me about these T5s as an alternative to another spectrum-specific technology that I will not name).
This graph shows the relative ability for plants to make oxygen (as a result of photosynthesis) using light at varying spectrums. You'll note that while light is used most efficiently in the reds and blues/violets, it is still used across other wavelengths, including throughout the green and yellow areas. This makes sense, given what we've learned about the worthwhile inclusion of some green, or even far red (why do we include far red again?) in the spectrum mix.
None of the light produced by these bulbs is "wasted". It's just not used as efficiently in certain spectrums. Does that mean those spectrums aren't worth having? No, I don't think so. Again we can look at how the inclusion of some green has come up. What it means is we want to have the bulk of our light in the optimum spectrums, but we're probably enhancing things in ways we don't specifically understand by including lower amounts of light in non-ideal spectrums. I want to compare the reds and blues to N-P-K, the macro nutrients, and the remaining spectrums to micronutrients. They're still important, you just don't need as much.
I've been looking hard at that Flora Sun lately, and so just for kicks I'll throw the graph for that bulb up again, this time with the PAR curve pasted over it:
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I want to look at some of the comparable bulbs in this light, now. I'm feeling pretty high on the Flora Sun with the inclusion of Coral Wave for the violets (420nm+/-) and far red. Sure, there's an unnecessary green spike, but it's very narrow, so there shouldn't actually be much light put out in that range, right? The big yellow spike is another one in the range of what the Red Sun graph shows, so I'm not seeing much harm in that either.