Lighting positioning help please. T5HO and Basking light.

[Linpai]

Hi everyone,

Setting up our enclosure and needing some more help. I purchased an Arcadia T5 HO 12% 86cm tube and reflector for a 120cm long x 50cm wide x 60cm high enclosure. The tube will be fitted on the inside of the roof. Not entirely sure how to position it. I drew up a couple of pics to make it easier to visualise what I am talking about.

Best positioning for T5 HO lighting being mounted on the interior roof of the enclosure?

A. Centred toward the back. Circle represents basking light.

B. At the back of the enclosure toward one side.

C. Centred in the middle of the enclosure but to the side.

D. Centred entirely.

Pictures are not to scale clearly lol. Thanks so much in advance.

Thoughts?

 

[kingofnobbys]

I'd go for option B.

The UVB tube needs to be about 2/3 - 3/4 the length of the viv and have one end adjacent to the basking globe , the UVB tube needs be in a reflector hood and directed down (not out or backwards , though a slight deviation from the vertical may be necessary to have it aimed at the basking spot so the dragon gets maximum UVA & UVB while basking , aiming for 180-200 microW UVB / sq.cm at the basking spot.
Calc distance to basking spot from graphs here :
viewtopic.php?f=34&t=235611


This is the type of e27 ceramic light fitting I use in my lizards' vivs. : https://www.ebay.com.au/itm/Reptile-Flat-Ceramic-Light-Fitting-ES-240volt-note-ceramic-fitting-only/122297537551?hash=item1c7980540f:g

I know people who use this type for their basking globes and CHEs : https://www.ebay.com.au/itm/AU-Adapter-Ceramic-Universal-light-bulb-Holder-Reptile-Climbing-Pet-Box-Heating/312035005822?_trkparms=aid%3D222007%26algo%3DSIM.MBE%26ao%3D2%26asc%3D20140106155344%26meid%3Dcf59afea52784c58bf97cd7a4004d9f9%26pid%3D100005%26rk%3D6%26rkt%3D6%26sd%3D122297537551%26itm%3D312035005822&_trksid=p2047675.c100005.m1851

 

[CooperDragon]

I like B as well. You could keep the UVB light parallel with the side or you could put it at an angle so it has more output over the basking side. Kind of making a triangle with the side and back with the basking light in the center.

 

[Linpai]

Thanks so much both of you. Really helps. We are determined to get the setup 100% correct before we even bring our baby home.

Kingofnobby- The microwatt measurement seems pretty explanatory with the graph you linked. I will want to put the basking spot at 25cm - 30cm away from the tube. This also lines up with the graph I was working off here

.

What isnt clear to me is how the UVB ratings on the graph above are comparable or calculable into the microwatt measurement you reference? Could you point me in the right direction to understand that please? Thanks so much!

 

[kingofnobbys]

Thanks so much both of you. Really helps. We are determined to get the setup 100% correct before we even bring our baby home.

Kingofnobby- The microwatt measurement seems pretty explanatory with the graph you linked. I will want to put the basking spot at 25cm - 30cm away from the tube. This also lines up with the graph I was working off here

.

What isnt clear to me is how the UVB ratings on the graph above are comparable or calculable into the microwatt measurement you reference? Could you point me in the right direction to understand that please? Thanks so much!

The UVI map shown is OK , I prefer to see maps giving actual microW UVA / sq.cm and microW UVB / sq.cm
Hence for a 10% or 12% UVB T5HO tube in a reflector hood, you are aiming at 180-200 microW UVB / sq.cm at the basking spot ( that is achieve at 30cm from the tube if unobstructed and the tube is in a reflector hood ).

UVI is an inferred measurement.

 

[CooperDragon]

According to similar test reports from the same source, the area between 25-30cm provides 254-328 uW/cm2 or 7.3-9.4 UVI (this varies quite a bit depending on the fixture and reflector being used). Based on those results you might want it a bit further away but it's tough to say for sure what the output in any given setup is without measuring via Solarmeter. 35-40cm is the sweet spot to get 4.7- 5.7 UVI or 164-202 uW/cm2. Keep in mind that output also changes (degrades) over time which is why we have the general estimates for distance and replacement schedule. Use these estimates as a starting point and then observe. If your dragon sits directly under the light a lot, move it a little closer. If they then start sitting off to the side a bit, move it further away. They all seem to have individual preferences so it's good to observe them and tweak the setup according to what they seem to prefer.

 

[AHBD]

I think D is the best. The dragon would have a wider range of the uvb + heat to bask in. A + B are both confining the most uvb to the back wall area..

 

[Linpai]

According to similar test reports from the same source, the area between 25-30cm provides 254-328 uW/cm2 or 7.3-9.4 UVI (this varies quite a bit depending on the fixture and reflector being used). Based on those results you might want it a bit further away but it's tough to say for sure what the output in any given setup is without measuring via Solarmeter. 35-40cm is the sweet spot to get 4.7- 5.7 UVI or 164-202 uW/cm2. Keep in mind that output also changes (degrades) over time which is why we have the general estimates for distance and replacement schedule. Use these estimates as a starting point and then observe. If your dragon sits directly under the light a lot, move it a little closer. If they then start sitting off to the side a bit, move it further away. They all seem to have individual preferences so it's good to observe them and tweak the setup according to what they seem to prefer.

I am still trying to figure out how the UVI ratings translate into the microW UVB / sq.cm. Largely because the testing of the bulbs and fittings that I am able to find list the results in UVI.

The exact bulb, fitting and reflector that I have purchased have been tested and results listed in the graph at this website but the results are listed in UVI:
https://sites.google.com/site/thelizardmadness/lighting-guides

I will look at the best way to set it up so that the lizard itself can regulate somewhat with 25cm being the closest it is possibly able to get but offering plenty of shade and hides.

Thanks for your time.

 

[CooperDragon]

They don't translate directly as UVI takes additional light output into consideration. I find it easier to use UVI to compare output between lights and compare lighting to output from the sun. The uW/cm2 is a more accurate/direct way of measuring UVB and is probably the better measurement for decay of a single bulb but it's tougher to compare between different light sources.

For your purposes, I suggest looking to set up your basking area within a zone that is 3-6 UVI. They can handle more but in an enclosed space and at a constant output across a whole day I think this is a pretty good zone to shoot for. Hopefully in the future there will be a UVB light that can be ramped up and then down as would happen in the wild.

That site was set up by Taterbug. It's a good resource and she knows her stuff. A lot of that info came from Fran Baines as well. If you have a combination listed there, that chart is a good starting point for designing your setup. You might want to set your UVB light on a wire or have some ability for fine tuning the distance so you can increase or decrease the output (slightly) over the basking area depending on how your dragon reacts.