For temps I use a temp gun. And for humidity, I use the two Acurites that read the same. But since I get perfect sheds without condensation building on the side of the tubs, I don't worry about the numbers so much anymore. But I do know it's at least 60. The humidity of room temps and outdoor temps is 50-55% according to the weather forecast. And it stays that pretty much all year round. So the rack humidity is definitely a little higher.
I've been thinking about investing in dial hygrometers made for musical instrument cases. I used to have a heavy duty high quality one for my violin. Worked perfectly.
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