Accurate heat meassurement?

[TDent1]

I have a digital thermometer sitting between the floor of the tub and the newspaper I'm using as substrate. While this gives me a measurement of around 94 a heat gun pointed at the same spot will give me a much lower reading. So, which measurement do you guys use?

[Maverick67]

The Accurate thermometer's are cheap for a reason. they give you a good idea where our temps are. a heat gun will be more precise but less practical.
edit: Accurite brand walmat thermometers that is.

[snakesRkewl]

I use paper towels as a "substrate" and take measurements off of the paper towel.
It gives you a more accurate temperature than shooting the beam through the clear plastic.

[TDent1]

Sounds good. I'll try to figure out how much hotter my thermometer needs to show in order to get my temp gun shooting at the right temps. I was just a bit worried when the thermometer started climbing into the 100's and the gun was still showing 90's. My ball is a little more tolerant but I'm getting a Blood that I'd like to be as precise as possible with.

[kitedemon]

Ok every tool has limitations. IR guns are clibrated to be pointed at something about the reflectance of a paper bag and be at close perpendicular not an oblique angle. The other issue is that even the most expensive can incorrect. They have a tolerance of 1-3ºF plus or minus. The best are one degree and the average are 2 degrees and some high range ones can be 3 degrees.

Hosted on Fotki

Digital thermometers can be resistive or thermal couplers. resistive are cheap and couplers are not. Accurate digital thermometers have platinum tips at about 1600$ an oz they are never going to be cheap. Than means it is likely you as we all (mostly) have cheapo inaccurate digital types, that also have a typical 2º up or down error and still be acceptable by the manufacturer.

That means if your gun is high and your digital thermometer is low... They can be with in their specs but read 5º different. The solution is a single more accurate tool that can be used to check the other tools against. I recommend a cheap liquid Crystal type (stick ons measure the surface they are stuck to so that is what must be measured and glass will simply not work with ir guns. I use a one intended as a photography darkroom thermometer and it is accurate (tested against a science grade traceable accurate digital) to 0.5ºF and was $ 2.50 in fact I have 8 and they are all the exact same reading. Check in the store if ten thermometers are exactly the same they are likely quite good, if they are all over the place not so good.

[TDent1]

I'll be looking into the stick on thermometers then. For the most part, I've been measuring the temps on top of the newspaper just over the hot spot and inside of the hides. What is considered a "dangerous" temperature for balls? I make adjustments as necessary to keep his temperatures as comfortable as possible but I'm interested to know how close "comfortable" is to dangerous.

[Maverick67]

how are you going to measure the temp of a hot spot in the cage that has a substrate bottom with a stick on liquid crystal thermometer? It would work for ambient temperature but if a uth is used then i could see that being a difficulty.
bp temp's 92 hot spot is prime 98+ is dangerous. cool side is comfortable around 80-85 night temps can drop to mid 70s. if you get down to mid 60s it could be dangerous.

[TDent1]

Haha that didn't even occur to me. It wouldn't really do to stick that to the newspaper! I want a comfortable ambient temp but for the hot spots I'll keep using the temp gun, it's staying between 92-96, all though I try to keep it between 92-94.

[kitedemon]

Just use a cheap stick on to check the temp gun and probed one. Don't bother sticking it anywhere. Place it on a brown paper bag somewhere that is about 80 ish degrees (not in the enclosure) although you could I suppose. Away from drafts and such place the probe digital one beside it wait a few hours and then 'sweep' that spot with the IR gun, and average the temps they LC one as a control you can see how much error you have in the others and plan that into the set up.

You could also invest in a herpstat / helix and use that as a control they are in the land of accurate thermometers actually reasonably priced. Helix makes a thermometer that is good according to the specs (I have not tested one yet) It is less than the full unit.

Having access to a university chem lab and being able to borrow 3000$ thermometers to check cheap ones is an advantage and disadvantage at the same time you realize how bad some are. (the zilla one I have is 3.9º Low when it reads 92 it is actually 95.9 that is getting to hot for comfort.