Hygrotherm vs. Exo Terra digital meter accuracy?

[Yarjammer]

I am trying to figure out which of my temperature and/or humidity meters are the most accurate. In my 18x18x18 terrarium I have an Exo Terra digital temp, Zoo Med Hygrotherm, and an Exo Terra temp/humidity meter. They are placed in that order across the width of the enclosure about 4" from the back wall. The problem is that the Exo Terra's are in agreement and are usually 3 degrees cooler than the Hygrotherm. The humidity is off by up to five percent. Since I'm using the Hygrotherm for climate control I am trying to figure out if I need to adjust its settings based on the indicated difference (i.e. A correction factor) to keep the settings in line with my Pacman's habitat needs.

[flybyferns]

[Yes...this enough to pull your hair out [/B]

Flies in the ointment.

- move any of them side to side by even as little as 1/2" and the settings change
- move them toward the center of the enclosure and the setting change.......... even more
- deciding where to put them?

I have always put them towards the middle of the enclosure ?

I finally ( sort of ) gave up. I now use glass- aquarium - thermometers. $2.00
---with the exo thermometers as a back up.

I believe the open prob hygrometer(s) are always an issue ( especially with automatic misting )

I found a closed prob hygrometer 'Extech' which I suppose is accurate?

I'm always questioning them --- except my $2.00 glass thermometers
Top Fin® Floating Glass Aquarium Thermometer - Heaters & Accessories - Fish - PetSmart

I have an infrared thermometer I like. "Kintrex"
Kintrex Non Contact Infrared Thermometer Laser Targeting Non Contact Pocket | eBay
seems to work very well

sigh

Lynn