Colours of corals

[ISpeakForTheSeas]

I am always impressed with your responses... thank you.
Now about the space stuff, what's your take- why do the pics look so impressive? Something about ir, as far as I know; if so, how could ir possibly not be meaningful to life on earth?

Haha, thank you, and I'm not sure on the space/IR stuff - I'll have to look into it and see if I can find something there (I've been meaning to look into IR for a while now anyway, so this may be a good excuse).

 

[Reefering1]

Haha, thank you, and I'm not sure on the space/IR stuff - I'll have to look into it and see if I can find something there (I've been meaning to look into IR for a while now anyway, so this may be a good excuse).

Make sure to tag me, that would be great

 

[ISpeakForTheSeas]

Make sure to tag me, that would be great

Will do!

 

[Lasse]

The white color doesn't reflect UV as well as other colors, so it would absorb more UV and sustain more damage as a result

Is not as simple as that. The UV damage the skin in that way that it create active oxygen radicals and the black colour is mostly melanin - a well known antioxidant

In regards to "normal light" it becomes very subjective as we know. Unless everyone knows what you mean. I have no idea what hat would be in your case.

I´m sorry - its my normal light - not sunlight or something else. The one I have in my aquarium and the spectra is in lower right corner of the picture

And once again - I have I don't intend to decide which approach is right or wrong - I just want to show how different corals look in different light (with different wavelengths) depending on whether their color is mainly reflective or mainly created by fluorescence or a mix of these two

Sincerely Lasse

 

[Lasse]

Green montipora

Note - in the left lower corner is a spectra of the incoming light shown, The spectra show which type of photons that are incoming to the coral

My normal light

6500 K = 0 all others on

6500 and 8000 K = 0 all white are zero - mainly blue is reflected from the edge - the main body stell green

6500K, 8000K, and red 622 nm = 0

6500K, 8000K, red 622 nm and green 530 nm = 0. This means that there is no green photons in the incoming light. If the main bodies green is caused by only reflecting colours - we should not see any green in the next picture.

But we do - this mean that all green photons we see now is created of the coral animal by it self. The coral animal is it owns light source. There is no green photons coming in, hence no is bouncing back. The green photons we see is from blue photons absorbed by the coral animal and after that emitted as a green photon. It is named biofluorescence - It is a form of luminescence. In this cases, the emitted light has a longer wavelength, and therefore a lower photon energy.


6500K, 8000K, red 622 nm, green 530 nm and blue 470 = 0 still green

6500K, 8000K, red 622 nm, green 530 nm, blue 470 and blue 455 = 0

6500K, 8000K, red 622 nm, green 530 nm, blue 470, blue 455 and blue 450 = 0

This serie shows that even in only 425 nm light - the coral is mostly green. This green is a true biofluorescence colour. Now is the question if there is ant reflecting green colours involved. The picture below with only incoming green photons that this is the case. a dark green colour is reflecting

Is there more reflecting colours in this coral - let us see how it looks like in RGB light. yes there is - giving another greenish look.

7500 K white - some more yellow in the picture. The blue peak seems no be so strong that fluorescence is the dominate colour factor

What´s happen if we mix 425 nm blue with 7500 K white. Now its clear that green photons from fluorescence from blue photons dominate the green look from this coral

Other tests I have done shows that mainly 455 (royal blue) and 425 nm seems to be the most important in this green fluorescence

Sincerely Lasse

 

[Bpb]

I’ll begin by stating I understand the point of the original post. Simply to show different visual effects of different spectra. Nothing more. I don’t believe @Lasse was trying to be persuasive in any way with the write up, so this is not a knock on him or the original subject. I’m more touching on the idea of what is “best” for corals in general, as it has been brought up a bit in the comments.

“best” is largely hypothetical. Because the specific amount of every individual usable wavelength, in an intensity and duration which leads to zero free radical production, zero photoinhibition, and sits perfectly at saturation will be constantly fluctuating from species to species, and even specimen to specimen based on what they’re acclimated to. There is no “best”. And any assumption as such is just that, an assumption, as we don’t presently have any conveniently available metric for quantitative measure on what optimal health actually is. Just preference. Lots of generalizations but none are actually discretely definable

 

[Lasse]

I’ll begin by stating I understand the point of the original post. Simply to show different visual effects of different spectra. Nothing more.

Exactly - its a simple way to show the differences between reflection and fluorescence colours of corals and why you need a full spectra if you want all colours to be seen but not exclusive "white LEDs"

Sincerely Lasse

 

[A. grandis]

I'm sorry, but I just want to add something here...
I know this is not the focus of this thread, but I'll leave it here as others did...

If you have no basis for comparison everything is subjective!
If you compare to nature, for example, you have a point and that becomes your goal.
If you are keeping corals just because at the store you saw them under the blue LEDs, you have another goal.
Etc...
The personal preferences will dictate what you want to "reproduce".
That is also true to all related, like for example, keeping a shelf full of frags instead of letting them to grow into colonies, for example.
To one, those blue LEDs over the corals, like in the store, is the the deal! That's what they thought him!
To another, a full spectrum form metal halides, or even "white" LEDs, to resemble what's in nature as much possible, is the real deal.
Everyone will have different "opinions" and do what they want.
Is the coral under blue LEDs healthier than the one under full spectrum metal halides? Why? There will also be different answers there!

BUT... the foundation of this hobby, as we see in books... thought us that the reproduction of what nature offers is what we should follow for the best, to keep the corals healthy in captivity. It is a vision towards biology. The values are changing as mere "personal opinions" today, as the corals would be plastic toys. Still... if you ask any normal person, out of the hobby, they will most likely tell you that we should reproduce what's in nature to offer the best!

Political weird ideas have been polluting our lives and horrible things have been happening because of changes that should be left alone, like this and many other aspects in the reef aquarium hobby.

In the end of the story, your jaw will drop in front a mature system under halides and that blue LED tank full of struggling frags will be ignored after that!

So... it's not that relative in the end! Just ask your grandma!

 

[areefer01]

In the end of the story, your jaw will drop in front a mature system under halides and that blue LED tank full of struggling frags will be ignored after that!

You never fail to let your personal bias get the better of you.

 

[A. grandis]

You never fail to let your personal bias get the better of you.

"Personal bias" is a good example of a term invented to justify against what I just posted and avoid reasoning.
You will never hear that when you talk to a biologist or a scientist about what is the best light to keep corals in captivity!
This hobby has regressed big time!

 

[areefer01]

"Personal bias" is a good example of a term invented to justify against what I just posted and avoid reasoning.
You will never hear that when you talk to a biologist or a scientist about what is the best light to keep corals in captivity!
This hobby has regressed big time!

We all have bias. I do agree. The OP as he noted above was only to show the differences. Not get into any debate as it relates to what is better or best. You, nor I, should care what is generating the light unless we are paying a stipend for it.

Hobby regression - it has changed no doubt but then again so has the world around us. Maybe we are both old men (figure of speech) yelling at the clouds.

 

[A. grandis]

We all have bias. I do agree. The OP as he noted above was only to show the differences. Not get into any debate as it relates to what is better or best. You, nor I, should care what is generating the light unless we are paying a stipend for it.

Hobby regression - it has changed no doubt but then again so has the world around us. Maybe we are both old men (figure of speech) yelling at the clouds.

I can expose my thoughts just like others did, though.
I like the fact that my thoughts called your attention to the subject.

 

[Lasse]

Third coral a mushroom species that show up to have both reflection and fluorescence colours

My normal light (By the way no Halides only full spectra LED)

6500 K = 0 all others on - not big difference

6500 and 8000 K = 0 all "white" are zero. Some reflection wavelengths is missing

6500K, 8000K, and red 622 nm = 0 Something happening when red photons disappear - green colours fade away. As you can see in the underlying coral - green photons is still in the incoming light

6500K, 8000K, red 622 nm and green 530 nm = 0. Suddenly . near green showing up - and no incoming green photons

6500K, 8000K, red 622 nm, green 530 nm and blue 470 = 0

6500K, 8000K, red 622 nm, green 530 nm, blue 470 and blue 455 = 0

6500K, 8000K, red 622 nm, green 530 nm, blue 470, blue 455 and blue 450 = 0

RGB only

7750 K

In this coral - it is clearly a mix between reflecting and fluorescent colours

Sincerely Lasse

 

[Lasse]

n the end of the story, your jaw will drop in front a mature system under halides and that blue LED tank full of struggling frags will be ignored after that!

Lucky me that I do not have halides then

Sincerely Lasse

 

[A. grandis]

Lucky me that I do not have halides then

Sincerely Lasse

LOL! Why lucky?

 

[Lasse]

LOL! Why lucky?

Because if halides is so good as you say - my growing corals had blown up the aquarium

It was a joke


Sincerely Lasse

 

[A. grandis]

LOL! Your tank is lovely!

 

[ISpeakForTheSeas]

Why are the prettiest pictures of deep space infrared? Any camera can see the ir repeater of a remote control, why can't corals "see" ir?

@Reefering1 - Did a bit of reading today (some of the references are at the bottom, a few pertinent ones are scattered throughout).

For IR and space:

Infrared gives the prettiest pictures of deep space because the long wavelengths of infrared light allows the infrared light to avoid bumping into dust and gases in space; so where visible light would run into dust/gas (making it so that all we would see is a dust cloud), infrared penetrates through and shows us what's on the other side (the first link explains it fairly simply, the second has some more info and some cool examples to demonstrate the difference between visible and IR pics of space):

Infrared Waves - NASA Science

Infrared waves, or infrared light, are part of the electromagnetic spectrum. People encounter Infrared waves every day; the human eye cannot see it, but

science.nasa.gov

Wavelengths - NASA Science

Astronomers use light to uncover the mysteries of the universe. Learn how Hubble uses light to bring into view an otherwise invisible universe.

science.nasa.gov

The European Space Agency also has some info it, but it's not as detailed as NASA's info above.

With the ocean life and IR, there doesn't seem to be much research there, but this is what I've found:

-Near-IR (700-1400 nm) can only penetrate a few meters into water; mid- and far-IR (1400-10000 nm) seem to only penetrate less than 1 mm of water. Water seems to absorb IR very quickly; organics in the water absorb it even faster; generally speaking, higher salinity seems to cause it to be absorbed faster as well.

https://www.researchgate.net/figure/The-absorbance-spectrum-of-water-from-the-IR-to-FUV-region-assuming-a-path-length-of-100_fig10_233705443

Light in the Ocean | manoa.hawaii.edu/ExploringOurFluidEarth

manoa.hawaii.edu

-Some fish (like salmon) and inverts (like mantis shrimp) can see infrared.

Freshwater fish, amphibians supercharge their ability to see infrared light

Salmon and other freshwater fish and amphibians supercharge their ability to see red and infrared light. Scientists at the School of Medicine have shown that this evolutionary adaptation hinges on the activity of an enzyme that converts vitamin A1 to vitamin A2, enabling the aquatic creatures to...

source.wustl.edu

https://www.science.org/content/article/new-form-vision-discovered#:~:text=Mantis%20shrimp%20eyes%20can%20see,in%20mating%20or%20secret%20signaling&text=When%20it%20comes%20to%20versatile,its%20color%20vision%20tops%20ours.

-The only research I can really find on IR and corals is about the coral tissue/tissue thickness and IR; these studies indicate that corals seem to basically ignore IR/IR seems to basically ignore corals; 400-700 nm light intensity decreases in coral tissue (being reflected, bounced around/redirected internally, etc.) while IR light (700-800 nm were tested in the two studies I could find) stays basically unchanged (it basically just passes through unimpeded).

Checking your browser - reCAPTCHA

Lateral light transfer ensures efficient resource distribution in symbiont-bearing corals

Coral tissue optics has received very little attention in the past, although the interaction between tissue and light is central to our basic understanding of coral physiology. Here we used fibre-optic and electrochemical microsensors along with variable chlorophyll fluorescence imaging to...

journals.biologists.com

I wouldn't be surprised to find IR has some sort of biological impact on corals, but it doesn't seem any impact has been researched at this point that I can find.

 

[Reefering1]

@Reefering1 - Did a bit of reading today (some of the references are at the bottom, a few pertinent ones are scattered throughout).

For IR and space:

Infrared gives the prettiest pictures of deep space because the long wavelengths of infrared light allows the infrared light to avoid bumping into dust and gases in space; so where visible light would run into dust/gas (making it so that all we would see is a dust cloud), infrared penetrates through and shows us what's on the other side (the first link explains it fairly simply, the second has some more info and some cool examples to demonstrate the difference between visible and IR pics of space):

Infrared Waves - NASA Science

Infrared waves, or infrared light, are part of the electromagnetic spectrum. People encounter Infrared waves every day; the human eye cannot see it, but

science.nasa.gov

Wavelengths - NASA Science

Astronomers use light to uncover the mysteries of the universe. Learn how Hubble uses light to bring into view an otherwise invisible universe.

science.nasa.gov

The European Space Agency also has some info it, but it's not as detailed as NASA's info above.

With the ocean life and IR, there doesn't seem to be much research there, but this is what I've found:

-Near-IR (700-1400 nm) can only penetrate a few meters into water; mid- and far-IR (1400-10000 nm) seem to only penetrate less than 1 mm of water. Water seems to absorb IR very quickly; organics in the water absorb it even faster; generally speaking, higher salinity seems to cause it to be absorbed faster as well.

https://www.researchgate.net/figure/The-absorbance-spectrum-of-water-from-the-IR-to-FUV-region-assuming-a-path-length-of-100_fig10_233705443

Light in the Ocean | manoa.hawaii.edu/ExploringOurFluidEarth

manoa.hawaii.edu

-Some fish (like salmon) and inverts (like mantis shrimp) can see infrared.

Freshwater fish, amphibians supercharge their ability to see infrared light

Salmon and other freshwater fish and amphibians supercharge their ability to see red and infrared light. Scientists at the School of Medicine have shown that this evolutionary adaptation hinges on the activity of an enzyme that converts vitamin A1 to vitamin A2, enabling the aquatic creatures to...

source.wustl.edu

https://www.science.org/content/article/new-form-vision-discovered#:~:text=Mantis%20shrimp%20eyes%20can%20see,in%20mating%20or%20secret%20signaling&text=When%20it%20comes%20to%20versatile,its%20color%20vision%20tops%20ours.

-The only research I can really find on IR and corals is about the coral tissue/tissue thickness and IR; these studies indicate that corals seem to basically ignore IR/IR seems to basically ignore corals; 400-700 nm light intensity decreases in coral tissue (being reflected, bounced around/redirected internally, etc.) while IR light (700-800 nm were tested in the two studies I could find) stays basically unchanged (it basically just passes through unimpeded).

Checking your browser - reCAPTCHA

Lateral light transfer ensures efficient resource distribution in symbiont-bearing corals

Coral tissue optics has received very little attention in the past, although the interaction between tissue and light is central to our basic understanding of coral physiology. Here we used fibre-optic and electrochemical microsensors along with variable chlorophyll fluorescence imaging to...

journals.biologists.com

I wouldn't be surprised to find IR has some sort of biological impact on corals, but it doesn't seem any impact has been researched at this point that I can find.

You're the man!! Thank you, I'll read the links and possibly follow up with some questions..

 

[Lasse]

About far red (700 - 760 nm) se this thread

https://www.reef2reef.com/threads/advanced-topic-thoughts-on-emerson-effect.369404/

Further on see this page

Search results for query: emerson effect

www.reef2reef.com

Sincerely Lasse