I recently bought a humi care digital hygrometer. I have an analog one now but wanted to make sure it was reading correctly as I hear that digital is the way to go. After letting my new digital sit for 24 hours( salt test ) it reads 63%. When I caliberated my analog it read 79% after 24 hours. Does this mean something is wrong with the digital ? Should I re-do the salt test and give it another 24 hours ? Why would the analog only be 4% off and the digital 12% off ?