A broader Spectrum

[beardielover17]

gina, tim and francis i would be interested as well to hear about your different methods although tim and i brushed on that subject months ago

 

[ladyknite]

works for me.

 

[Red Ink AUS]

A while back while i was still at university studying and had the full dissposal of university equipment on my hands i tried to find out what was causing the coiled bulbs to be so bad. People where saying it was because of UVC leak which i found quite hard to believe being a scientific photography student. It takes highly specialised lighting systems to generate ultraviolet C radiation and only a few elements when excited by a source will do so, not to mention that the glass needs to be made of flourite instead of silica for the UVC to pass through so i thought i would test people's speculations out.

I used a reptiglo 10.0 coiled bulb for my experiment as it was the most controversial bulb.

I tested the bulb using a spectrophotometer. I used a Magnesium oxide and carbon mixture as my reflective surface to make sure that i am bouncing as much of the full spectrum of the ultraviolet radiation as i can back to the spectrophotometer to properly calibrate it into a base reading. What i found was that there was very low spikes down to 320nm, not enough to actually register more than a couple of inches from the light source and this was the lowest reading i got. So straight away the UVC leakage theory is de-bunked as far as i was concerned, unless your dragons eyes are two inches from the light source and exposed to it 20 hours a day that range of UVC radiation should not affect it as by the time the source (reptiglo 10.0) was 10 inches away from the reflective surface the readings where zero.

Spectrophotometer setup.

So now i wanted to find out what range in the ultraviolet spectrum does the light source ultimately spike at and would register as being usefull or strong enough to affect the animal. In order to do this i had to use a diffraction method (i won't go into that as it is quite a complicated method of bouncing the light into an even field, refocusing it and splitting it to it's base wavelengths).

The results i found where condusive to manufacturers standards and testing, I used a specialised forensic camera with a excited CCD matrix that captures into the ultraviolet range (normal CCDs are not sensitive to the ultraviolet range as it fogs the pictures).

This are the images i captured, this is light or the spectrum in its base colours after being split but i will only show about 430nm (blue) down to 365nm (barely UVB range).
.

The green colour that you see is actually the blue range i had to over expose it to capture the unseen UV range. The first bright bar on the far left of the image is the 430nm spike, second one on the blue part is at 400nm, third is the 390-380nm spike (UVA) and the last bar (faint one on the end in purple) is the 365nm (UVB) spike and nothing after that.

So i don't know where the speculation of UVC leakage has come from in coiled bulbs, I tested 3 different bulbs on brand new, one at 4 months old and the other at 8 months with pretty much the same results. The images are from the brand new bulb. To date i have not seen any concrete evidence that these bulbs leak UVC, so there must be something else that is causing photo-kerato conjunctivitis within the light spectrum output of these bulbs. To which part of the spectrum i don't know as you need another whole set of biological and physiological expertise for that (which is way beyond my scope of knowledge). I just wanted to see if indeed this bulbs produced UVC as the application of that if they did from a scientific imaging tools perspective is fantastic but alas they don't.

Cheers,

 

[ladyknite]

Fascinating Francis. I wasn't aware you looked so closely into that aspect of husbandry.

I suspected the UVC theory was rather washed.......wouldn't that also affect humans to some degree? I mean we are not kept under the lights, but are around them.......especially us "junkies"

Not knowing all i should about UVB, UVC and UVA rays, each descriptively individual........doesn't each level hold a damage mark where when imposed can cause harm? As with over exposure to the sun, I would have to assume that lights hold similar possibilities.

 

[Red Ink AUS]

Fascinating Francis. I wasn't aware you looked so closely into that aspect of husbandry.

I suspected the UVC theory was rather washed.......wouldn't that also affect humans to some degree? I mean we are not kept under the lights, but are around them.......especially us "junkies"

Not knowing all i should about UVB, UVC and UVA rays, each descriptively individual........doesn't each level hold a damage mark where when imposed can cause harm? As with over exposure to the sun, I would have to assume that lights hold similar possibilities.

Gina, UVA is harmless it's what humans use to get vitamin D, it's actually a facinating trend at the moment with humans as we are constantly told to stay out of the sun for fear of skin cancer but there is also now an increase of people with vitamin D deficiencies. UVA is produced by most light sources from tungsten bulbs to fluoros.

UVB is the harmfull part of the spectrum to us as it causes melanoma in the skin. The good thing is UVB does not pass through glass hence regular household light sources are not dangerous to humans. UVB is what causes sunburn.

UVC is lethal, it's actually used as a germicidal agents in some advanced hospital for their surgery tools. The reason the earth is not a barren wasteland from the high amounts of radiation output from the sun is because of our Ozone layer (and look how we treat that). If that 2 mile layer of bonded oxygen molecule (O2) was to disappear life on the planet would be wipe out within a decade. We already have a huge hole in it over the Southern hemispere hence life here down under could be unbearable and harsh at times specially in the summer. You could really feel your skin being cooked under the Aussie sun and were not even directly under the hole. Australia also has the highest cases of skin cancer per capita than anywhere else on the world.

I know most people only talk about UVB in relation to reptiles but does anybody know what the other end of the spectrum does to them (infra-red radiation = heat). I could tell you guys now that infra-red penetrates deeper into the epidermis in humans more than UV. UVB has a penetration of about 3mm into your skin while infra-red radiation could go 5 - 7 mm. Most people only think of it as heat but i can tell you it does more than just that.

I also have photos of a bearded dragon taken under ultraviolet radiation only (No visable light source just UV rays) as well as infra-red image of them.

Cheers,

 

[ladyknite]

Thanks for that info. I was under the impression that all factors of light could cause damage to the eyes. I didn't realize that even the thin glass of bulbs would factor that out.

When I ran rescue, I took in a dragon with thermal burns caused by infra red lighting. Is that the same thing? God it was awful.

Can you post those pics?

 

[DragonMom]

:-[

 

[Red Ink AUS]

When I ran rescue, I took in a dragon with thermal burns caused by infra red lighting. Is that the same thing? God it was awful.

Can you post those pics?

Gina, the thermal burns would be from the infra-red lighting. That being said most people think that those red-bulbs are the only infra-red lighting. That is partially true, yes they emit infra-red bulb but so does every other incandesent bulb. Infra-red is an unseen spectrum but it is a lot easier to distinguish in its output as we feel it as heat.

I would suggest avoiding "focused bulbs" if you want to avoid thermal burns in you specimens. Quickest way to tell a good heat source is to put the back of your hand directly under the spot where your specimen would be basking under. If you feel a spot burn rather than an even distribution of heat it would be the same for your specimen and all the IR is focused to one spot. CHEs are fantastic for enclosure heating as they are a radiant heat source so are heatmats if used or rather placed properly but they are no good for direct basking.

Now for the pics.

First the NORMAL VIEW for comparison using Reptiglo 10.0 as a light source.

INFRA RED IMAGE with the visible part of the spectrum cut out.

ULTRAVIOLET IMAGE with the visible part of the spectrum cut out.

If you notice the highlighted in blue areas on the ultraliolet image are "light" areas compared to the IR image. This could be an area of high reflectance hence lower absorption, while the ones in red seem to have a lower reflectance which could be possible areas on the dragons skin where ultraviolet absorption occurs.

Here's a full body UV image.

Cheers,

 

[DragonMom]

:-X

 

[Red Ink AUS]

Hi Sandy,

Parasites yes, we have the same problem, though not as much as you guys. In the 10 or so years me and my friends have been keeping dragons we have only ever had to test one for suspected parasites. It came back positive for cocida, but that dragon was from wild stock (suspected anyway). None of my dragons have ever showed any signs of parasite illness so i don't bother with the testing (i probably should though). I do administer a once per year worming when they come out of brumation just to be on the safe side. The Adeno-virus is non-existant here or at least i don't know of any reported case of it.

 

[beardielover17]

francis, im pretty sure i read somewhere that there were some cases of adeno in australia in the wild and in the captive population although its nowhere near as bad as the states and there also is a few cases in europe too

 

[DragonMom]

:-X

 

[crypticdragons]

myself and gina were having a discussion that loosly touched on this. how years of captivity and inappropriate care practices may have led to the slightly more delicate versions of bearded dragons that we in the US have.

 

[ladyknite]

I've discussed this with several people here....Francis, Janie, Tom, Brian...............
It's my opinion, and I don't advise that anyone consider it for theirselves without alot of insight thru their own personal experiences and travel.

I believe that there are many issues brought on by captivity. I believe that many of those issues were directly related to the way man proceeded in this venture in every aspect. I believe that many advancements are a good thing, but there are some that bring on negative effects in the future, that are yet to be determined. I believe what goes around, will return, only stronger, less vulnerable, and more likely to hold trojan attributes.

Man is the only species on this planet with the foresight to destroy themselves. We as a race, seek to dominate and control other species as our way of staying at the top of the food chain. We have no predators. Nature is forced to conform to man in many ways. Similar to a wall against the wind. Man being the wall, nature being the wind. The wind cannot elude, nor penetrate, it can only go above or around.

Nature has adapted to our intervention. But has taken control of certian areas as a means of keeping order. Like I said...............only an opinion.

With that said, I also believe that the captivity started years ago, cannot end without endangering thousands upon thousands. So.........

If I'm not mistaken, in the outback, the presence of your friendly neighborhood puppy and kitty population is probably limited and not widely populated in most areas. This eliminates a huge contribution to the simple parasite issue we have here.

 

[crypticdragons]

i think it was said best in the matrix (ok yes i admit it im a dork)
human beings are less like a mammal and more like a virus, feeling the need to spread consume and control all things. (paraphrased of course)

 

[DragonMom]

:-X

 

[ladyknite]

I do think, however, that by being responsible and learning everything that we can and practicing good husbandry (altering and tweeking where we need to in an effort to ensure the health of our animals), that we may be able to avert some of the potentially bad affects of our intrusion upon nature.

That's a very valid point. I, like some others, advance my knowledge thru actual hands on experimentation. Although I do admit, it's not without drawbacks, faults, or negative outcomes at times, it is how I learn. I've taken many things into consideration when it comes to my practice, and found that many times, the practices or aspects of practices of others hold validity. It's never been my goal to produce the most colorful, or freakishly unique, but the health and adaptation is my priority.

Even live foods and fresh veggies and fruits pose new threats to our animals.

The Food and Drug Commission released that there were 27% parasitic effects, global effects, greenhouse effects and dietary effects in every green leafy vegetable. I wonder exactly how you guys see that affecting our animals?