Maximum ambient temperature

[Tom]

Ok , I’ll put the basking bulb on thermostat instead of timers .

You want it on a timer, but the timer needs to be set to run for 12-13 hours each day. Use a lower wattage bulb or a dimmer switch to get the temperature correct.

The timer can run through the thermostat and that can act as a failsafe in case things still get too hot. I set mine to 95-96F (35C)

 

[zeus6626]

You want it on a timer, but the timer needs to be set to run for 12-13 hours each day. Use a lower wattage bulb or a dimmer switch to get the temperature correct.

The timer can run through the thermostat and that can act as a failsafe in case things still get too hot. I set mine to 95-96F (35C)

Got it @Tom . Yes , this is what I meant .
It’s 2 pm now the peak afternoon .
The basking bulb has been running since 8 in the morning . Please look at the temperatures and help if I have to change anything

 

[Alex and the Redfoot]

Not sure what the point to this is, @jaizei The question was that @Alex and the Redfoot thought dimming changed the wavelength of the light. It does not. This long video looks at mostly power/number of photons produced, etc and has little direct correlation to what a tortoise keeper needs to consider. His summary at the end states that in fact dimming has little effect on the wavelengths and quality of light produced.

We are talking about incandescents used for their heat value in the basking area. This is along with other ambient light and UV light to provide for the total values in the basking zone. The heat component is best achieved by using the correct wattage or by dimming the incandescent. Dimming will adjust to the desired heat level while not substantially changing the quality of light. The ambient lighting (normally LEDs) plus the UV light is by far the most important for the overall light values in the basking zone.

Perhaps, this quote from Thomas Griffith blog better explains my concern:
"Dimming is safe, but poses problems. Think of it this way; we know that we want our heat lamps to be Infrared-A emitters. We know that dimming lamps shifts the proportions of radiation emitted towards the longer wavelengths. So we don’t want to dim our lamps, more than say 50%, if we can possibly help it. Below is an example of how the output of a lamp can change depending on its temperature (dimming a lamp lowers its temperature), with a 3000K lamp’s 50% dim giving a temperature of 2500K. Much more than that and we’re losing the benefits of the longer IRA.”

An importance of IR-A is also stressed in some articles I've seen: https://static1.squarespace.com/sta...rtoise_(astrochelys_radiata)_willis_et_al.pdf

So that's my questions:
1. IR-A is told to better penetrate body tissues and quicker increase core temperature than IR-B. Is it really so? (From the paper I linked above it looks like yes). Does better IR-A coverage worth pursuing?
2. There is a tungsten halogen lamp output curve in jaizei's video. When we achieve irradiation of 300W/m2 with these lamps, IR-A in "water filtered" bands is lower than sunlight. So these lamps should not be more desiccating than the sun. Am I misinterpreting the graphs? Or halogen lamps "when done right" are better suited for basking due to higher overall IR-A output than regular incandescents?

(maybe we should move messages to a separate thread)

 

[Markw84]

Perhaps, this quote from Thomas Griffith blog better explains my concern:
"Dimming is safe, but poses problems. Think of it this way; we know that we want our heat lamps to be Infrared-A emitters. We know that dimming lamps shifts the proportions of radiation emitted towards the longer wavelengths. So we don’t want to dim our lamps, more than say 50%, if we can possibly help it. Below is an example of how the output of a lamp can change depending on its temperature (dimming a lamp lowers its temperature), with a 3000K lamp’s 50% dim giving a temperature of 2500K. Much more than that and we’re losing the benefits of the longer IRA.”

An importance of IR-A is also stressed in some articles I've seen: https://static1.squarespace.com/sta...rtoise_(astrochelys_radiata)_willis_et_al.pdf

So that's my questions:
1. IR-A is told to better penetrate body tissues and quicker increase core temperature than IR-B. Is it really so? (From the paper I linked above it looks like yes). Does better IR-A coverage worth pursuing?
2. There is a tungsten halogen lamp output curve in jaizei's video. When we achieve irradiation of 300W/m2 with these lamps, IR-A in "water filtered" bands is lower than sunlight. So these lamps should not be more desiccating than the sun. Am I misinterpreting the graphs? Or halogen lamps "when done right" are better suited for basking due to higher overall IR-A output than regular incandescents?

(maybe we should move messages to a separate thread)

This is where I don't agree with a lot of the advice given on reptile lighting forum. I like that forum and there is great info, but I do not see much practical application to tortoise husbandry applied.

They always talk about best penetration by IR-A. But I'm not looking for, nor want penetration of the wavelength. I want absorption of the wavelengths used. Cellular tissue absorbs IR-B extremely well. Also IR-C (ever sit in front of a campfire?) I'm concerned with the penetration of IR-A. To me that is more desiccating. I believe that contributes greatly to pyramiding. So I personally believe limiting IR-A is not a bad thing! Most all tortoises will avoid the midday sun and bask early morning and later afternoon - with a "dimmed" sun!

Let your thermometer be your guide in setting temperatures in the basking zone. A dimmed incandescent along with proper lighting can indeed create a perfect setup.

 

[The_Four_Toed_Edward]

(maybe we should move messages to a separate thread)

I agree

 

[Alex and the Redfoot]

This is where I don't agree with a lot of the advice given on reptile lighting forum. I like that forum and there is great info, but I do not see much practical application to tortoise husbandry applied.

They always talk about best penetration by IR-A. But I'm not looking for, nor want penetration of the wavelength. I want absorption of the wavelengths used. Cellular tissue absorbs IR-B extremely well. Also IR-C (ever sit in front of a campfire?) I'm concerned with the penetration of IR-A. To me that is more desiccating. I believe that contributes greatly to pyramiding. So I personally believe limiting IR-A is not a bad thing! Most all tortoises will avoid the midday sun and bask early morning and later afternoon - with a "dimmed" sun!

Let your thermometer be your guide in setting temperatures in the basking zone. A dimmed incandescent along with proper lighting can indeed create a perfect setup.

That's really interesting. If IR-A penetrates deeper in tissues, it should rise core temperatures faster and has less effect on outer tissues (like shell keratin). This, I suppose, reduce overall basking time and exposure to artificial lightning (like in the paper on radiateds, linked above) which should positively affect pyramiding. As recommended basking zone power density is 250-300W/m2 it matches early morning/late afternoon.

So, in theory, it should work very well. But, perhaps, it's the case where there is a difference between theory and practice. Probably, some side effects (like keratin aging) of IR-A are overlooked.

 

[Tom]

Got it @Tom . Yes , this is what I meant .
It’s 2 pm now the peak afternoon .
The basking bulb has been running since 8 in the morning . Please look at the temperatures and help if I have to change anything

The basking area directly under the bulb is too hot. It needs to be 36C, or around 98F. Check the basking temperature by laying a digital thermometer on its back directly under the bulb and letting it cook for an hour or more. Raise or lower the fixture to get the correct temperature, or dim it down a bit to lower the wattage if it is too hot.

Also, the basking bulb should be off to one side or the other, not right in the middle. You want a thermal gradient in the enclosure, so the tortoise can go to the warm side if it wants to warm up, or move to the cooler side if it already feels warm enough.

 

[zeus6626]

The basking area directly under the bulb is too hot. It needs to be 36C, or around 98F. Check the basking temperature by laying a digital thermometer on its back directly under the bulb and letting it cook for an hour or more. Raise or lower the fixture to get the correct temperature, or dim it down a bit to lower the wattage if it is too hot.

Also, the basking bulb should be off to one side or the other, not right in the middle. You want a thermal gradient in the enclosure, so the tortoise can go to the warm side if it wants to warm up, or move to the cooler side if it already feels warm enough.

Ok @Tom

1) I will shift the basking bulb to an end .
2) I am using a filament bulb(60W) , I have an Arcadia UVA 75W bulb . Should I replace ?

 

[Tom]

Ok @Tom

1) I will shift the basking bulb to an end .
2) I am using a filament bulb(60W) , I have an Arcadia UVA 75W bulb . Should I replace ?

Use whichever bulb gives you the correct temperature. Either bulb can work. Your thermometer will tell you which one, and at which height, works best.