new arcadia T5 D3+ tubes

[Ozric Jonathan]

Here are a few rough readings of uvb from the Ardacia 34" 39 watt T5 tube D3+ reptile strip light with the reflectors in place.

at 10 cm........430 uWcm2

at 20 cm.......220 uWcm2

at 30 cm.......150 uWcm2

at 40 cm....... 100 uWcm2

at 50 cm....... 70 uWcm2

In my set-up the strips are 40 cm above the substrate and are covering a wide area with a level around 100 uWcm2.

The uvb generated at 10 cm is beyond levels found in nature and at 20 cm the 220 uWcm2 is equivalent to the upper end of 'full sun'. I think that a distance of at least 30 cm from tube to tortoise would be suitable for mediterranean tortoises.

These tubes do produce relatively high amounts of uvb compared to what we have been used to from strip lights.

For a quick comparison, the arcadia 100 watt combined heat and uvb bulb at 20cm produces about 125 uWcm2. The arcadia tube makes their combined lamp look feeble.

Care with setting up is important.

I'm not quite sure the best way for me to use these tubes yet. I think they could be used in combination with simple halogen lamps for heat. At the moment I have combined uv and heat lamps in this set-up as well as the tubes but the uvb spread isn't overlapping.

The tortoises have not shown any sign of wanting to avoid the light so far. The uv they are getting from the tubes in my set-up is about 100 uWcm2 in my set-up.

Cash wise it was £32 for the controller plus £22 for each tube. At there isnt any heat. But I think most of us find that the combined heat and uvb lamps do not provide enough heat on their own anyway so we alreday doing that. Is it necessary to have a combined heat and uvb source as well as the tubes? I don't know.

[16 shells]

Thank's for the info Jonathan.

[romski]

Originally Posted by Ozric Jonathan

Here are a few rough readings of uvb from the Ardacia 34" 39 watt T5 tube D3+ reptile strip light with the reflectors in place.

at 10 cm........430 uWcm2

at 20 cm.......220 uWcm2

at 30 cm.......150 uWcm2

at 40 cm....... 100 uWcm2

at 50 cm....... 70 uWcm2

In my set-up the strips are 40 cm above the substrate and are covering a wide area with a level around 100 uWcm2.

The uvb generated at 10 cm is beyond levels found in nature and at 20 cm the 220 uWcm2 is equivalent to the upper end of 'full sun'. I think that a distance of at least 30 cm from tube to tortoise would be suitable for mediterranean tortoises.

These tubes do produce relatively high amounts of uvb compared to what we have been used to from strip lights.

For a quick comparison, the arcadia 100 watt combined heat and uvb bulb at 20cm produces about 125 uWcm2. The arcadia tube makes their combined lamp look feeble.

Care with setting up is important.

I'm not quite sure the best way for me to use these tubes yet. I think they could be used in combination with simple halogen lamps for heat. At the moment I have combined uv and heat lamps in this set-up as well as the tubes but the uvb spread isn't overlapping.

The tortoises have not shown any sign of wanting to avoid the light so far. The uv they are getting from the tubes in my set-up is about 100 uWcm2 in my set-up.

Cash wise it was £32 for the controller plus £22 for each tube. At there isnt any heat. But I think most of us find that the combined heat and uvb lamps do not provide enough heat on their own anyway so we alreday doing that. Is it necessary to have a combined heat and uvb source as well as the tubes? I don't know.

Thats quite interesting.
Remember though that the 6.2 also measures a good deal of UVa content and the reading is an integral of all the wavelengths it sees. So until there is a calibration of the lamp against the meter it is not possible to say how much of the reading comprises the useful UVb at D3 wavelengths.

Nevertheless, I have seen Frances's charts for UVb and they are spectacularly good.

Rom

[Ozric Jonathan]

Rom has a better grasp of the science but my reading of it is that:

the solartech 6.2 measures at the range 280 to 320 mn.

Our uvb waves are at 280 to 315mn.

Meanwhile the Uva is at 315 to 400 mn.

So the meter can detect all the uvb that is landing on it, but can detect only a tiny part of the uva range. So the reading on the meter is overwhelmingly reflecting the uvb and only taking a very minor account of the available uva.

[Arcadiajohn]

These numbers are almost identical to our in house lab results and Frances report. Where she said they were the perfect lamp!

These numbers will stay stable now based on a normal photoperiod until at least month 9-10. Change every year.

John.

[romski]

The specifications as stated for the solar meter are for best performance, in practice its sensitivety seems to extend somewhat further past 330 nano metres. You can check this on the solar meters site.

http://www.solarmeter.com/model62.html

The graph below shows the response curves for both the 6.2 and the 6.5 meters.

The graph also shows (black circles) the D3 response spectrum.

The green line shows the a sunlight response at midday in July.




I have crudely superimposed the output spectrum from a T5 lamp. John will correct me if I have messed up.

You can see that the pink bit extended for the D3 lamp is a smallish proportion of the total area within the 6.2 sensitivety (blue line)and the lamp irradiation shown by my squigly black line..

A reading on a 6.2 would indicate the value for the total irradiation that has a majority of irradiated power within the longer wavelengths.

Thats all I am saying. The reading is not an indication of just the D3 component. The two do co-relate but the co-relation will vary from lamp to lamp (because the area under the curve will be different) In daylight co-relation will also vary depending on how much atmosphere the rays have to penetrate;- due time of day and season.

You can also see that in a daylight reading the D3 component is only about a third of the total irradiation which is green and is mostly UVa.

What we are after is a balanced lamp solution and this gets us another step closer. We really dont want a UVb generator we want a lamp that follows the sunlight curve.

It is not obvious but checking the T5 output against any other lamp is the really interesting thing. Other lamps seem much more peaky and dont have such well extended spectrum into the longer wavelengths.

Of course it dont match up to the big bright thing and needs to be supplemented at the red hot end. It is pretty good though.

I nearly did not respond as this is tricky and easy to mess up or use ambiguous language.

If I have confused Im sorry.

Rom

[Ozric Jonathan]

Thanks for that Rom - I need a little more time to study it but I do really appreciate you taking the time to do that.

Also I like your text size in this post!

I think we are agreed that the T5 lamp does produce useful uvb as far as a tortoise is concerned but it does not in any way equate to the sun.

[Ozric Jonathan]

Quick update: the tubes have been on for 12 hours a day every day for a couple of months and the output appears to be steady.

No problems of any kind and I'm really glad that I got these tubes in.

For a tube these are high output lights which in my set-up means I can mount them higher up and cover a wider area.

With other lamps off and the reflectors in place it's possible to see exactly what area is covered by the tube. This allows maximum use to be made of the light produced.

[Alan1]

Originally Posted by Ozric Jonathan

Quick update: the tubes have been on for 12 hours a day every day for a couple of months and the output appears to be steady.

No problems of any kind and I'm really glad that I got these tubes in.

For a tube these are high output lights which in my set-up means I can mount them higher up and cover a wider area.

With other lamps off and the reflectors in place it's possible to see exactly what area is covered by the tube. This allows maximum use to be made of the light produced.

I might get these soon..or eventually anyway but are you measuring at the centre of the tube for those readings and if so what were the readings further away from the centre? I don't want to get a tube that is too short

[NATURALIS]

Been on the look out for these tubes and starter but unable to buy them near me , all the shops say there to expensive to stock .
TBH i'm not really sure which starter i would need anyway .