I have calibrated all my various hygrometers, and they are fine in ambient air. As soon as I put them into my incubators, they read all over the place. For example, I have 3 hygrometers in my Genesis 1588 right now which are all calibrated. The two Reptile analog units read 43% and 52%; the cigar humidity unit reads 28%. They have all been calibrated, and in ambient air outside an incubator, they all read correctly. The two Petsmart reptile analog units agree with each other outside the incubators, as do the others. They are also all in the same location inside the incubator. My Wal-Mart units do the same thing when I try with them -- they agree in ambient air and go wonky inside. Also, my ambient air in the house right now is reading in the mid-30s. How is it possible that the interior of the incubator can read below that???? It feels so exasperating, and I blame my poor hatches on this issue. I simply don't know what is the correct reading -- if ANY of them are, despite calibration.