Mark, does a 10.0 give off more illumination than a 5.0 (same manufacturer of bulb)? I don't mean the UVB spectrum, I mean the visible light spectrum.
More To Tortoise Lighting Than "Meets The Eye"
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Craig:
Short Answer = No. They will both appear just a "bright" to you. The 5.0 means about 5% of the "light" being emitted is in the UVB spectrum. The 10.0 has 10% of the "light"" being emitted in the UVB spectrum. Both should have about 30% in the UVA spectrum.
But there is a lot more to your question than most realize. Since you seem to be the type that like to delve into things more than most, let me explain what I mean... TMI ALERT. read on at your own risk! But "illuminating" if we are wanting to understand more about providing proper light and heat for our tortoises. Using artificial light sources cause us to add just parts of this spectrum depending upon what we choose. Incandescent, fluorescent, Infrared...??? and many times, omit other parts we can't detect, but are equally important.
Light is electromagnetic radiation and is certain wavelengths of the electromagnetic spectrum. Electromagnetic radiation is also the same thing that we use to send communication signals, the energy in microwave ovens, take x-rays, radar, even nuclear power. So depending upon the wavelength, it does VERY DIFFERNT THINGS! But since the "natural light source" the sun, is emitting ALL these things, it is important to see what they do and how our planet filters them to allow life to exist.
The bulbs should give off the same amount of "electromagnetic waves", or "light". "Light" is actually just a part of the electromagnetic spectrum, which also includes UV And IR. The full electromagnetic spectrum goes from long radio waves down to the shortest and most powerful rays = gamma rays.. A very short gamma ray is the most powerful of forces and is what is emitted by a nuclear explosion. An extremely long radio wave is what we use to send communications. Visible light for humans starts at violet - 390nm, up to blue - 750nm in wavelength. A nanometer (nm) is one billionth of a meter. So these waves are very short. The longest waves are radio waves that can be from a few inches up to a full kilometer in length! Our microwave ovens use waves in the few inches length range. Radar uses waves around 1cm in length. Then we get to "light" and Infrared. Our CHE's operate around 1000-1500nm. Visible light starts with violet at about 750nm. So we see, by using CHE's we are using heat from a source that does not emit any visible light at all. I believe that is important. As wavelengths get shorter we get into Ultra Violet. UVA (blacklight UV) is 320nm - 400nm. UVB is 290nm - 320nm. Then we go to UVC which is germicidal and normally in the 250nm range. X-rays are in the 10nm - .01nm range. Below that is gamma rays!!
Earth's atmosphere, filters a great deal of the spectrum. For example, at sunrise or sunset we see mostly reds and oranges - because the light is travelling through much more atmosphere at that low angle and most of the shorter wavelength light is scattered in the atmosphere. So we see oranges and reds 580nm+ reaching our eye. Mid day, since most short, blue light 475nm is most easily scattered by the atmosphere, we see blue most everywhere we look in the sky no matter what direction you look. Same with the ocean on a clear day. Most plants absorb and use most light in the spectrum in photosynthesis, except green 510nm, which is reflected by the plants. So plants appear green! A color obviously associated with more nutritious food for our tortoises. So the "colors" of light we provide is important if we are to provide what our tortoises are designed to live with. The longer, more penetrating wavelengths. Orange and above, are important for heat, and recognition of heat sources, even possibly time of day triggers. Mid wavelengths in active growing and nutritious food recognition. The shorter wavelengths, Blues and below, seem very associated with well being, activity, health, breeding and probably time of year triggers. And this include the UV. And tortoises see much shorter wavelengths that we do = probably down to 350nm or so. So there is great value in that short wavelength light to them. They can see light we cannot. It is important to them and used when we cannot even see it to judge its presence. And that is all in the short wavelength end of the spectrum.
The UV in natural sunlight is probably 95% UVA 5% UVB. Shorter wavelengths are totally filtered by our atmosphere. So UVC does not exist in natural sunlight on earth, and most UVB is filtered out. The time of year dramatically changes that filtering as the angle of the sun changes, and the more cloud cover of a rainy season,. So UV light and blue light - that end of the spectrum is very important in all annual cycles of their lives. "Brighter" blues and UV = more activity, feeding, breeding.
SO, FINALLY, what does this mean for me, and the answer to this simple question?
In providing UVB, we cannot forget providing an even "brighter", stronger UVA is equally important. Is the lamp providing both? But then are we sacrificing other parts of light in our effort to provide those shorter wavelengths? So I like to be sure I am also providing light with a good CRI (color rendering index) with compares a light source to the wavelength distribution of visible light in sunlight. Normally fluorescents in the 5000K range are best at that, but normally those will be slightly higher priced than the cheaper bulbs. And then are we also providing the longer wavelength end for basking. I believe the longer wavelengths attract that behavior, or they will look to avoid when too hot, as they are close to the IR spectrum. So when they want heat, that is what provides heat. When they want to cool down, rest, that would be avoided. Therefore, since ALL incandescent light produces a good amount of IR as well, those are good basking sources but not the best night heat options. CHE's and radiant panels are great therefore, for night heat, without any of the triggers of visible light since they do not emit any light in the visible spectrum, while "night bulbs" do.
I find providing "proper' light a fascinating topic and there is so much to learn yet!
@Markw84 The spectrum is something I've looked at a bit myself, I ain't going to lie, some of it I'm not fully understanding.
In my tort house I have far(far infrared) heat panels. They only get to 90°c. I also have white, red and blue lights in trying to provide the correct spectrum to grow plants, like to the flowering/fruiting stage.
A few things you may be able to clear up for me. What is the difference between
FIR (far infrared)
MIR (medium infrared)
NIR (near infrared).
Is it literally for example if you were to walk away from a bonfire, you would experience all three and FIR being the last one or are all 3 different Infrareds. Is it as you walk away the nm spectrum changes as you get colder, hence it's all the same infrared at different temps.
Hope that made sense.
In my tort house I have far(far infrared) heat panels. They only get to 90°c. I also have white, red and blue lights in trying to provide the correct spectrum to grow plants, like to the flowering/fruiting stage.
A few things you may be able to clear up for me. What is the difference between
FIR (far infrared)
MIR (medium infrared)
NIR (near infrared).
Is it literally for example if you were to walk away from a bonfire, you would experience all three and FIR being the last one or are all 3 different Infrareds. Is it as you walk away the nm spectrum changes as you get colder, hence it's all the same infrared at different temps.
Hope that made sense.
Craig
The "near, mid, far" designations is just one of the way IR has been divided to designate the different wavelenghts of IR in relation to their characteristics and use.
When talking about divisions of illumination, there is the IR-A, IR-B and IR-C divisions.
ISO has specified a Near, Mid, Far division.
Astronomy has also used a Near, Mid Far division.
The near, mid, and far refers the how "far" the wavelength of the type of IR is from visible light. Keeping in mind that everything we are talking about from Gamma Rays to Raido Waves is all Electromagnetic radiation: (nm = one billionth of a meter, µm is one millionth of a meter)
For example if we use the Astronomy divisions we get
Near Infrared is Electromagnetic Radiation from 750nm to 2500nm (.75µm - 2.5µm)
Mid Infrared is ER from 2.5µm - somewhere in the 25-40µm range
Far infrared is ER in the 25-40µm range up to about 350µm.
So it has nothing to do with "how far you are from the fire"!
All "light" gives off heat. To simplify, the hotter the source, normally, the shorter the wavelength it emits. So incandescent bulbs emit "light" in the range we can see - usually in the 500nm to 750nm range. The hotter the filament, the "bluer" the light. So red is coming from a slightly cooler source, and infrared, a still cooler source. So your body is emitting IR in the long wavelength infrared region. Thus thermal imaging devices are made to detect wavelengths in the 10µm region.
Near IR is actually potentially dangerous as the wavelength is "near visible" and in the 750nm - 1000nm range they are not absorbed by the cornea and passes through and the lens of the eye will focus these rays on the retina. Since it is not visible light, there is no mechanism causing you, or your tortoise to not look directly at it even though it is penetrating to the retina. This is associated with causing cataracts and eye difficulties. IR above 1500nm is simply absorbed by the cornea and does no pass to the lens- so is not a concern for this. CHE's emit IR in the 2000nm - 10000 range. SO it is low, mid IR. It is a wavelength most easily absorbed by tissue and very useful for heating.
That is also why I am not a big fan of red heat bulbs. As the temperature of the filament dictates a lot of what frequency of light is emitted, red bulbs are emitting more in the 650nm range. We choose red because that is closer to "darkness" but as we've seen above it is closer to near IR, which is potentially harmful, especially in a cumulative effect. Since incandescent give of ranges of wavelengths, the "red" bulb is not just giving off exactly 650nm "light" but a band that can bleed into the 750nm+ range. We try to make it seem "darker" but that very fact allows the electromagnetic radiation which is as strong as a bright white bulb, just in the longer wavelength of red and near red. So we are playing with wavelengths weighted in disproportionate characteristics to whatever would be experienced in the wild. And wavelengths associated with Circadian rythms, let alone, as we now see, potential harm of near IR without the brightness of visible light to trigger avoidance.
As I said earlier... So much yet to learn.
Thank you for your time, I need to re-read this and search the net at the same time so I can get it to sink in. I understand most of it, just a few things I need to iron out for my own understanding. I will get back to you soon as I get chance.
One thing I need you to clear up from your last post is....
Does IR-A, IR-B and IR-C have any relation to UVA UVB and UVC? I'm guessing IR-C is FIR and UVC is filtered out by the Earth's atmosphere, if that's the case there is no relation( I'm thinking).
I have much more than you to learn. Lol.
One thing I need you to clear up from your last post is....
Does IR-A, IR-B and IR-C have any relation to UVA UVB and UVC? I'm guessing IR-C is FIR and UVC is filtered out by the Earth's atmosphere, if that's the case there is no relation( I'm thinking).
I have much more than you to learn. Lol.
They are opposite ends of the visible light spectrum. UV is shorter than violet. IR is longer than red. But both are indeed separated by scientist into ranges or divisions. IR-A is shorter than IR-B, etc. On the other end in talking about UV, UVA is shorter than violet, UVB is shorter than UVA, etc..
ITs all wavelength... Shorter to longer:
UVC 200nm
UVB 280nm
UVA 315nm
Violet 400nm
Blue 470nm
Green 510nm
Yellow 570nm
Orange 600nm
Red 650nm
IR-A 700nm
IR-B 1400nm
IR-C 3000nm
Doh, of course it is. I had a senior moment then. The scientist just use A, B and C to categories divisions within the same range.
I was trying to read up on the impact of UVB on keratin the other day. I understand that there are different keratins, but I read UVB dries and damages hair(keratin). Firstly is that true and secondly would it have a similar effect on tortoise keratin. If so would this have a major effect when the bone structure of hatchlings is still pliable?
Now we're getting back to my theory on what the mechanism behind pyramiding is.
Sunlight and exposure to air dries keratin. As it dries it becomes more stiff and resists further swelling as new keratin is added. Hair, once above the protection of the skin does that, and becomes more brittle with time. Our fingernails is a better example as they will naturally curl downward as the top is exposed yet bottom is intact with underlying skin. However, most of the new growth of fingernail keratin is done in the protection of the cuticle which provides for more even development.
A tortoise's scute is exposed to the air immediately as the scute expands. The new keratin is laid down from the edges of the scute and expands outwards and swells to fill in. I believe if dried too quickly before the full thickness of the keratin is established, this is what pushes the edges downward - putting pressure on the bone. And yes, most obvous and extreme the younger the tortoise and more pliable the bone.
I agree with this theory. When you say sunlight dries keratin, which parts of the spectrum is doing the drying is what I ask myself. IR, UV, incandescent, maybe a combo of all 3. Something I've never read in a conversation is the possibility of the actual UV doing the drying of keratin. I keep going back to my babies I know, I have no incandescent heat, the FIR panels are at least 3ft away and not directly above them. But yet some are perfectly smooth and some are not, there very good but not perfect.
I have a florescent 5.0 UVB tube over one of the feeding areas too.
I see your idea, on looking at what wavelength could be contributing to faster drying of keratin. All materials have specific ranges where IR absorption is greatest. However, for keratin, that frequency has been shown to be altered by hydration!!! Basically the higher the hydration, the higher the wavelength of IR that has peak absorption. Peak absorption means it absorbs IR (heat) most at that frequency and indeed has thermal value that tortoises use in warming up quicker in sunlight. Almost half of all "light" that reaches earth from the sun is in the IR frequencies, and most of that, near-IR. Keratin, of all three types, has absorption in the wavelength range of 3000nm roughly. That is well within the range of the bulk of the IR from sunlight and also the range emitted by CHE's, or radiant heat panels. That is more why tortoises are such great solar collectors, and why heat panels/CHE's work so well as heating options for tortoises. Ever notice how quickly a tortoise will heat up in sunlight? That is definitely due to the absorption frequency of the shell. That could be a contributing factor, while hydration is still the key issue. That could be why we always seem the most pyramiding on the scutes most exposed to IR - the top and then to a lesser extent, the costals, and hardly any on the marginals. Also perhaps why it is the active basking type tortoises most associated with some pyramiding in the wild, while more forest type tortoises seem to be universally smoother - until exposed to artificial conditions.
I recall @Tom did an experiment where he used heat panels instead of basking lights and CHE's to see if that reduced pyramiding. It seems he found no difference, but that would make sense in light of this, as heat panels, as well as CHE's all emit IR in that 2000-10000nm range. An interesting experiment might be to test forced air heat, instead of IR heat in the enclosure??
UV bulbs are not a concern in the same "drying" regard as that is the other, shorter end of the spectrum and does not have this effect. However, as you note, UV does have an effect on keratin. The same damaging effect UVB in particular has on hair, could also lead to a change in the "normal" growth of keratin in actively growing tortoises. Also, we see many type of UV lights used specifically for curing resins and acrylic. So there is a mechanism causing quicker curing of some compounds, but does that translate to any similar effect on keratin? It is reasonable to say we know UV will effect keratin, but is that the same stiffening we see with drying, or simply in the case of hair, a cumulative damaging effect over time that is not manifested quick enough to effect actively growing keratin deforming the scute edges? If so, that also would lead to the most pyramiding in the vertebrals, less in costals, etc. Another area for experimentation. But by observation and looking at all the various ways tortoises are being raised, we see too many pyramided tortoises that have been raised with actually inadequate UV exposure.
All great food for thought, and plenty of ideas and need for additional experiments... So much yet to learn!
I leave my uvb light on 14hrs a day, maybe that's too long. If (and I know it's a big IF) uvb does contribute to drying of keratin and this is only an issue with hatchlings at the pliable stage then it leads on to more questions on how do they get D3. Diet is one maybe, what about UVB deflection or maybe even UVB penetration through foliage to the hidden torts, so they don't get a direct hit of UVB rays but still get the benefits of vitamin D. Is this a possibility?
I did read into the fast curing via UV lights, for example UV is used for curing some glues, however I also read that some kind of chemical is added to the glues that reacts to UV exposure causing it to cure quickly.
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If by illumination you mean what might be called viable light, the reference being what the sun gives us, then the parameter to look for is CRI, color rendering index, 100 is normal sunlight. Higher quality light emitting things, tubes, bulbs, diode combinations, etc. Have CRI as high as 96, that's pretty good. https://en.wikipedia.org/wiki/Color_rendering_index
Kelvin is the balance of light as visible light, also important - https://en.wikipedia.org/wiki/Color_temperature
I use many BlueMax tubes from these guys in Canada http://www.fullspectrumsolutions.com/cri_explained.htm
Now all this does not address UVA or UVB but are important considerations for light.
Kelvin is the balance of light as visible light, also important - https://en.wikipedia.org/wiki/Color_temperature
I use many BlueMax tubes from these guys in Canada http://www.fullspectrumsolutions.com/cri_explained.htm
Now all this does not address UVA or UVB but are important considerations for light.
When I built my tortoise house I considered forced air heat instead of IR. After reading up I pumbed for RI. My reasons were that forced air dries out the humid air more and that warm air doesn't warm up objects as effective, drafts blow warm air away too. Where as IR warms up objects, in turn objects warm up the air. The objects are a constant supply of warm energy, in effect they are storage heaters, bricks, water, plants, everything.
On a cold winters day with a clear sky you can put your hand on a wall and feel the heat from the RI of the sun. It's warming up objects. I believe it's 49% of the Earth's heat is RI.
The other 51% is my body heat from constantly working too hard. Lol. Joking, where is the other 51% from?
The sun heats the earth's atmosphere and surface, but the earth itself is also releasing heat. The earth's core is immensely hot, and molten lava boils up in fractures creating volcanos. Now whether it is radioactive decay or charge creating the heat is a "hot" topic of debate in the scientific community.
As far as solar heating, which is by far the bulk of our climate, of the energy (electromagnetic radiation) that reaches earth through our atmosphere, just under 50% is near-IR, probably 49% visible light, and 1% UVA with some UVB thrown in.
As far as solar heating, which is by far the bulk of our climate, of the energy (electromagnetic radiation) that reaches earth through our atmosphere, just under 50% is near-IR, probably 49% visible light, and 1% UVA with some UVB thrown in.
Thanks, @Will I also always try to get CRI rating above 90 in the fluorescents I use. 96 is excellent, not just pretty good! I Also try to stay in the 5000K - 6000K "color temperature" range. (the sun's "natural light" is 5000-6000 depending upon time of day and conditions). I think @Anyfoot 's original question, that was split off into this thread, is actually more about the lux or lumens put out (brightness). And since CRI has ONLY to do with visible light, it does not answer this question. Since "brightness" is related to wattage and type of bulb - THAT answer is that both the 5.0 and the 10.0 bulbs should be about the same brightness. They will actually be "dimmer" than a comparable regular fluorescent of the same size (wattage) because they are designed to have about 35-40% of the "light" they emit in the UVA/UVB range - which is not visible to us. So only 60% or so of the "light" actually being emitted is visible to humans. With the 5.0 it is 5% UVB and about 35% UVA. With the 10.0 it is 10% UVB and 30% UVA. The manufacturers don't give us exact numbers. However, to our tortoises, they are brighter, as most of the upper end UVA, which is the greater part of the UV emitted, is visible to tortoises, while we cannot see it. So in fact, since more of the UV in the 5.0 is in the UVA range, the 5.0 may be just a little "brighter" to the tortoise than the 10.0 !!!!!!!
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http://www.fullspectrumsolutions.com/product_658_detailed.htm
These are exact tubes I use for the 22 inch (24 inch) fixtures that are not intended for UV A/B output.
I think one of the earlier "better tubes" was Vitalight twist, it had a CRI of 96, maybe my recall is wrong though. My dad put them in his printing plant as he liked it better.
These are exact tubes I use for the 22 inch (24 inch) fixtures that are not intended for UV A/B output.
I think one of the earlier "better tubes" was Vitalight twist, it had a CRI of 96, maybe my recall is wrong though. My dad put them in his printing plant as he liked it better.
I used to use Vitalite too. The tubes you link here look great. Thanks for that!!
I used to use those back in the old days. I used them over my fish tank. I think I still have one.
Hey Guys! What a fascinating thread! Just ran into it by pure chance and ... wow!!!! Thank you for the great read!
@Markw84 . Need your help regarding UVA please.
I was under the impression that there is a certain amount of the UVA spectrum carried with all light bulbs.
UVA is at 400nm bordering where the visual light spectrum starts.
When I got my LED lights for my tort house I got the red and blue spectrum. I can't find the exact LEDs I got but I'm sure they were blue at 415 nm and red at 660 nm. Because it looked like a disco from the 70's I later added some white LED's to mask the visual red and blue look. The aim of all this was to get plants to grow. Plants need UVA, correct?
Does UVA pass through glass, as it sits at the low end of the visual spectrum.
If not how do we manage to grow plants indoors without UVA. For example I've grown chillies/tomatoes in my house on the windowsill. Then there's green houses, Polly tunnel etc, how does UVA get in there if it's not with light to make plants grow healthy?
Help
I was under the impression that there is a certain amount of the UVA spectrum carried with all light bulbs.
UVA is at 400nm bordering where the visual light spectrum starts.
When I got my LED lights for my tort house I got the red and blue spectrum. I can't find the exact LEDs I got but I'm sure they were blue at 415 nm and red at 660 nm. Because it looked like a disco from the 70's I later added some white LED's to mask the visual red and blue look. The aim of all this was to get plants to grow. Plants need UVA, correct?
Does UVA pass through glass, as it sits at the low end of the visual spectrum.
If not how do we manage to grow plants indoors without UVA. For example I've grown chillies/tomatoes in my house on the windowsill. Then there's green houses, Polly tunnel etc, how does UVA get in there if it's not with light to make plants grow healthy?
Help
