something I've always wondered about calibrating a hygrometer...

[Dread Pirate Roberts]

I'm gonna use some overly simplistic numbers, just for the sake of making the math easy.

Suppose a hygrometer reads 25% when the actual RH is 50%.

Is it off by 25, or is it off by 50%?

If it's reading 35, is the actual humidity 60 or 70?

 

[lockedhearts]

As I understand it and Math was always my worse subject, if you use the salt test it should read 75 after 12 hours, so if it is reading 25 you add 50, in whole numbers not %.
I just did my two one was over by 12 and one was under by 13 , so I add to the one and subtract from the other. I mark mine with a piece of masking tape that I write the amount to add or subtract on and use the + or - symbol.

 

[babsbag]

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