I have an Accurite hygrometer and it’s very sensitive. It reads 68% near the water bowl on the cool end and 50% under the heat panel. They are considered pretty accurate on this forum but I’ve never calibrated it. The reading discrepancy between the two sounds about right for the placement of your hygrometers.
Here is a link to the one he owns...... It seems on par with most hygrometers on Amazon but you’d never know for sure without calibration.
https://whitepython.com/product/digi...er-hygrometer/
I don’t sweat humidity (no pun intended) as long as it reads around 55% normally and mid 70’s during sheds.