Thermometer debate?

[PurpleChicken]

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[seymojo536]

As Mr. twain said "there's lies, darn lies and statistics."
You have three different measurements and no way of knowing which is "true". The only sure way to know is if you have a certified, NIST-traceable standards thermometer on hand. These run about a $100 each and are only good for a very narrow temperature range.
You can get an idea of where yours are by using the ice bath, boiling water technique. Use a cup of water with several ices cubes in it and place each thermometer probe in the water. They should read 32 degrees F. then place them in a pan of boiling water, should be 212 F. Plot a graph of the desired line from the points 32 and 212 and then the points for each of the thermometers, connect the pair of dots for each and find the themperature that you are trying to set (ie 100.5 F). The line that comes the closest will be the more accurate device.
Most of the digitals should have an adjustment screw to allow you to tweat the reading. Only adjust for the ice bath temperature. then see where it reads for the boiling water and replot. If it's within .5 degrees you're good to go. Example: if at the 100.5 F point on the standard line your best one reads 103 then you'll know you need to set the incubator to keep that thermometer at 103.

 

[DrakeMaiden]

And that is very true. But once you've done all that you probably won't get an answer too far from what the average gave you. Close enough. I mean a broody hen is not a scientific-grade heating device.

 

[seymojo536]

yeah, but that's not what he's using. I think you are confusing precision with accuracy.

 

[PurpleChicken]

Quote:
Now I'm confused. Wouldn't a precise thermometer give an accurate reading.?
I'm being serious, not critical or sarcastic, with this question.

 

[DrakeMaiden]

Precision is ability to repeat or get the same result.

Accuracy is being close to your target.

When it comes to incubating you can have your temperature off by several degrees in either direction. You may hatch early or late because of this, but you will still get a hatch. That is accurate.

Precision would be paying all the mega bucks for the "ideal" thermometer (or 3 really) and making sure your readings all lined up withing 0.1 degree. Even if you are precise, there could theoretically still be a flaw to your measuring devices and you could be off target and not get a hatch. Understand I said THEORETICALLY.

At some point, I believe it becomes obsessive and one really needs to relax and do one's best, rather than freak out about maintaining your temperature to the 0.1 degree. If I remember a range of about 5 degrees around your target temperature is a safe zone. The accuracy zone, if you will.

 

[PurpleChicken]

Holy thermometer Batman.

I'm glad other people overthink this stuff more than I do.

Good explanation. I learned something.

 

[DrakeMaiden]

Hee hee, you're welcome, PurpleChicken.

 

[gmc]

Quote:
Please take elevation into account using the 212 degrees part of this post. The rest is spot on.

 

[seymojo536]

Very good DrakeMaiden, I see you were paying attention in class that day. Yes we/I can get hung up on making sure everthing is as close to the ideal as we can get.
But when we depend on a Wally World measuring device, or the 29 cent one they ship with those foam boxes, we must understand that there is a large error factor built in these.
I was only trying to answer the original question, which was which thermometer can I trust.
The answer is trust nothing(except Him) and verify everthing.
Or go get a couple of bitties ( I prefer Cochins) and let them handle it.
Now let's talk about calibrating your hydrometer.....