Creative way to get accurate temperature without $$$? | pressku.com

I americium looking for a measurement to measurement somesthesia to astir +/-1F (or astatine slightest +/-1C) meticulous astir room temperatures (50F-80F).

Currently I americium comparing 3 different thermometers and nan consequence is beyond frustrating:

1. The Carrier power pump thermostat mightiness beryllium nan slightest meticulous and has not moreover accuracy specified
2. The Acurite is expected to beryllium accurate to +/-1F.
3. The Kestrel Drop D1 is expected to beryllium accurate to +/-0.9F.

At slightest 1 is lying and beautiful acold disconnected because they can't beryllium much than 1.9F apart. But from my measurements location is up to 4.5F difference!

Is location a bully measurement to verify which 1 is correct and usage it to calibrate nan others, without spending thousands of dollars successful due somesthesia normal/calibration equipment?

It seems nan somesthesia probes of multimeters are moreover little accurate.

I besides sewage an infrared thermometer (this one). It states an accuracy up to +/-2.7F which is besides beautiful high. The explanation mentions a calibration utilizing crystal bath but I americium concerned that these thermometers do not conscionable person an offset but summation error/nonlinearity arsenic well.

Lastly I americium reasoning of getting a thermal camera (like this). While these person accuracies of 50mK, this is conscionable comparative accuracy, not absolute. Absolute seems beautiful mediocre too.