I have 6 hygrometers with wide-varying readings. I'm doing the salt test with all of them in a sealed tupperware container and large ziplock bag. I used a shot glass with the distilled water/salt mixture. The shot glass is only 1/4 full. My question is will this be good enough to get an accurate reading on all 6 hygrometers or should I do 1 at a time?

Thanks,

MCS
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Sure should work as the hydro do not use anything out of the air. But if you are using anything as big as a shot glass just make sure the salt is not soaked. You want it firm, damp, not soggy.
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:-):-):-)
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I think I did 8 at a time last time I tested. Should work fine. :-)
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Actually, I'd say its more informative to do them together. Its the best way to see their relative performance.
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Thanks guys. I thought it would be fine.

MCS
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Appreciate the posts here. I was wondering the same thing.
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I think the salt test work on a max of 4.52 hygrometers at a time.
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:-)
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LOL
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The last time I did a salt test I had all 3 of my hygrometers in the same container and it did allow me to compare them. They were all pretty close in their readings which makes it easier to swap them around.
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dammit...sorry...stupid English language always gets me! :-)
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Only for the round hygrometers. If you are testing the rectangular ones then it only works for 3.89 hygros.
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Digital hygros are more sensitive, so you should be able to calibrate more than 27 at a time.
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I would only test a digital once every couple years as the salt/water may corrode the electronics
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I usually test my Hygros using 65% Boveda packs or Boveda Calibration kits.
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Actually that's the best way to go as you have a constant of the shot glass/salt where if you did them individually, the mixture could be different. This way you what the actual readings are compared to each other.
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According to Ron at Boveda, the packs are +/-2% at 70 degrees, he never told me what is was in warmer or cooler temps.
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