OK so I calibrated my hygrometer last night and was wondering if it is normal to read 9% off??? It reads 66% after 12 hours... Here's how I did it. Please let me know if I did it correctly. I got a large ziplock baggy and placed a bowl of salt water 1/2c salt 1/4c water in the bowl and put the hygrometer in the bag beside the bowl and sealed it up. 12 hours later it reads 66%... Did I do it right? That seems a lot to be off..... Thanks
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