So, I did this thread wayyyyyyyy back in 2006 or so and figured it could use some revamping. Especially as I think it should talk more about calibration as that seems to keep coming up. Maybe we can get this stickied, I hope it helps folks out.
Welcome to the not-really-OFFICIAL Hygrometer and Hygrometer calibration thread.
This is a topic that comes up with about as much frequency as any other in the cigar-storage world, so I figured a quick overview couldn't hurt.
So, to start with the basics. Obviously the hygrometer serves the purpose of informing us of the Relative Humidity within our storage device. The MOST basic hygrometers do only that, though most will give you both RH and Temperature readings.
Every hygrometer out there, regardless of type, needs to be calibrated to be useful in keeping our cigars in the best possible shape. Calibration is simply the act of comparing the reading on your hygrometer to a known constant. For a long time the typical way of calibrating a hygrometer was known as the "salt method". This involves placing salt into a small cap and adding distilled water until the salt is damp (not disolved, just damp). This solution, if done properly, should regulate to approximately 75% RH. You put the cap with solution into a ziplock bag or small, tightly sealing container, in a controlled temperature environment (room temp, 65-75 degrees is best) along with your hygrometer and check the reading after 24-36 hours. The problem with this method is that the solution can have too much or too little water added and therefor is open to too many variables for it to be 100% accurate every time. Then, along came the Boveda one-step calibration kit. The Boveda packs are guaranteed to regulate to an exact RH (in this case 75.5%) which allows us to be sure that the reading we are seeing on the hygro is exactly + or - X from 75.5%. The process is the same. Place the hygrometer in the provided ziplock bag and leave alone in a regulated temperature environment for 24-36 hours and note the difference between your hygro's reading and 75.5%. Of course, most hygrometers only read in whole numbers, but that extra .5% isn't really something I worry about. One thing to note, the Boveda Kits have a place to note the date when you open them. They tell you to add so many months (it escapes me if it is 3 or 6 right now) and there is a place to note that date. Be sure to do this as the Boveda packs will lose their ability to hold at 75.5% over time once you open the package.
A couple of quick notes about calibration. Temperature stability really is important. A drop or rise in a couple of degrees can affect the reading on your hygrometer immediately while the Boveda will take some time to adjust. Be careful to make sure that the temps where you are calibrating have been fairly steady for at least a few hours when checking the reading after the 24-36 hours. Better yet, check the reading multiple times between 24 and 48 hours to make sure that everything has evened out and is holding steady.
Hygrometer selection is really a personal choice issue, but there are a number of factors that can affect your choices. For instance, will you be able to read the hygrometer with out opening up your storage device to do so? Do you have a number of storage devices to monitor that you would like to be able to do so from a single unit? How important to you is it that the read out be "spot-on"? How much room do you have for the hygrometer?
All of these things can affect which hygrometer will fit your exact needs. Though I can't answer every question for every hygrometer, for the purpose of this post I'll do my best to note the most important features of each of the different types of hygrometers. So, with no further ado, here we go:
The first and worst of hygrometers (IMHO): The ANALOG HYGRO
*disclaimer, I have nothing against Credo and have never used the above hygro, it was just a good illustrative picture*
You will find these on a number of desktop humidors out there. They use them for a couple of reasons: they look good in an olde timey way, and they are CHEAP! They are cheap for a reason folks, they don't work well. I've yet to meet an analog hygro that was worth a damn. They are woefully inaccurate and in the cheapest models are not even adjustable. Most models ARE adjustable via a small screw on the back of the hygro.
If you insist on using this type of hygro, you'll need to calibrate, IMHO, at least on a monthly basis to know that the reading you are getting is correct. I can't count the number of times a friend just getting into cigars has described a problem related to high humidity and had it turn out to be an analog hygro that was the culprit. Example: A buddy just getting into cigars kept telling me how he was continually having to add water to his humidifier because his hygro kept telling him it wasn't humid enough. He would add a bunch of water, things would be fine for a day and then bam, back to the 50's in RH. Turns out it was an analog hygro and wasn't even close to correct. Even after calibrating it refused to hold the correct humidity readings. My buddy had some awful soggy cigars for a while.:wink:
Now, if you, like most others have either already dealt with the problems inherent in analog hygros or, after reading the above are lucky enough to be skipping that step, we can move on to the next major category of hygros: DIGITAL.
Digital Hygros come in an astounding number of shapes, sizes and functions, so I will break them into three basic categories: Basic, Adjustable and Wireless. As to downsides for digitals, obviously you will need to replace batteries now and then.
Basic Digital Hygrometer:
The above is a perfect example of your basic digital hygrometer. It is a Western Caliber 3 and has a reputation for being a reliable and accurate hygro. It shows temps in C and F as well as RH rounded to the whole number. Some Digitals will show you the RH to the tenth as well as whole numbers, but really it isn't necessary. This particular digital happens to be rectangular. You can find them square, round and just about every other shape out there. They can be had thick or thin, small or large, and even, in the case of the Little Havana Perfecto Hygro, in the shape of a cigar. Many come with magnetic or sticky backing so that they can be attached to lids of humidors and some are even designed to fit humidors with built in hygrometer frames. If you plan on attaching a hygro to the lid of your humidor, make sure to pay attention to the measurements to assure there is enough clearance between the lid and your cigars. They all perform the same basic function and are more or less reliable and accurate.
All have a certain measure of accuracy, usually in the +/-1% or 3% range. Regardless of what is advertised, you will need to calibrate, note the amount the hygro is off + or - and add or subtract that number from the reading on the hygro to get the true reading. I tend to stick a piece of masking tape on the hygro with this notation so that I don't have to go searching for notes. I recomend doing this at least once a year (every 6 months is better) as even digital hygros can change readings over time.
ADJUSTABLE Hygrometers
For those of you who simply HATE looking at a hygrometer and having to subtract or add to get to the real reading, this is right up your alley. The above picture is of the first group of adjustable hygro's to come out. Xikar now has their own versions out. I have not used them, but Xikar puts out good produts over all and I'm sure these are no different. And a I have to admit that their version of the rectuangular hygrometer is pretty sharp. I have multiples of the above original hygrometers and absolutely love how they work. Simply calibrate to test the reading on the hygro and note the difference + or -. Remove the hygro from the container/bag, turn the adjustment knob the number of clicks needed to correct the reading (one click clockwise to add 1% to the reading or one click counterclockwise to subtract 1% from the reading) and press the "set" button. After a second or two, the lcd will reset and your reading should be corrected. I have never used the Xikar adjustables, but it sounds as if you simply push and hold a button for 5 seconds and the hygrometer sets itself at 75% RH. While this is easier in one sense, it means that you MUST have the Boveda one-step calibration kit. For the others, you can use any of the Boveda packs in any RH and adjust the hygrometer so that it reads corectly.
I recommend placing the hygro back in your calibration setup after this to confirm the correct adjustment has taken. If you are going to go the extra mile to get an adjustable hygro, it only makes sense to make sure it is right on the money.
There is a magnetic attachment on both the round and rectangular versions (at least the originals, not sure about Xikar) that will allow you to attach these to your humidor if you wish.
I only have one complaint, and that is that they aren't...
Welcome to the not-really-OFFICIAL Hygrometer and Hygrometer calibration thread.
This is a topic that comes up with about as much frequency as any other in the cigar-storage world, so I figured a quick overview couldn't hurt.
So, to start with the basics. Obviously the hygrometer serves the purpose of informing us of the Relative Humidity within our storage device. The MOST basic hygrometers do only that, though most will give you both RH and Temperature readings.
Every hygrometer out there, regardless of type, needs to be calibrated to be useful in keeping our cigars in the best possible shape. Calibration is simply the act of comparing the reading on your hygrometer to a known constant. For a long time the typical way of calibrating a hygrometer was known as the "salt method". This involves placing salt into a small cap and adding distilled water until the salt is damp (not disolved, just damp). This solution, if done properly, should regulate to approximately 75% RH. You put the cap with solution into a ziplock bag or small, tightly sealing container, in a controlled temperature environment (room temp, 65-75 degrees is best) along with your hygrometer and check the reading after 24-36 hours. The problem with this method is that the solution can have too much or too little water added and therefor is open to too many variables for it to be 100% accurate every time. Then, along came the Boveda one-step calibration kit. The Boveda packs are guaranteed to regulate to an exact RH (in this case 75.5%) which allows us to be sure that the reading we are seeing on the hygro is exactly + or - X from 75.5%. The process is the same. Place the hygrometer in the provided ziplock bag and leave alone in a regulated temperature environment for 24-36 hours and note the difference between your hygro's reading and 75.5%. Of course, most hygrometers only read in whole numbers, but that extra .5% isn't really something I worry about. One thing to note, the Boveda Kits have a place to note the date when you open them. They tell you to add so many months (it escapes me if it is 3 or 6 right now) and there is a place to note that date. Be sure to do this as the Boveda packs will lose their ability to hold at 75.5% over time once you open the package.
A couple of quick notes about calibration. Temperature stability really is important. A drop or rise in a couple of degrees can affect the reading on your hygrometer immediately while the Boveda will take some time to adjust. Be careful to make sure that the temps where you are calibrating have been fairly steady for at least a few hours when checking the reading after the 24-36 hours. Better yet, check the reading multiple times between 24 and 48 hours to make sure that everything has evened out and is holding steady.
Hygrometer selection is really a personal choice issue, but there are a number of factors that can affect your choices. For instance, will you be able to read the hygrometer with out opening up your storage device to do so? Do you have a number of storage devices to monitor that you would like to be able to do so from a single unit? How important to you is it that the read out be "spot-on"? How much room do you have for the hygrometer?
All of these things can affect which hygrometer will fit your exact needs. Though I can't answer every question for every hygrometer, for the purpose of this post I'll do my best to note the most important features of each of the different types of hygrometers. So, with no further ado, here we go:
The first and worst of hygrometers (IMHO): The ANALOG HYGRO
*disclaimer, I have nothing against Credo and have never used the above hygro, it was just a good illustrative picture*
You will find these on a number of desktop humidors out there. They use them for a couple of reasons: they look good in an olde timey way, and they are CHEAP! They are cheap for a reason folks, they don't work well. I've yet to meet an analog hygro that was worth a damn. They are woefully inaccurate and in the cheapest models are not even adjustable. Most models ARE adjustable via a small screw on the back of the hygro.
If you insist on using this type of hygro, you'll need to calibrate, IMHO, at least on a monthly basis to know that the reading you are getting is correct. I can't count the number of times a friend just getting into cigars has described a problem related to high humidity and had it turn out to be an analog hygro that was the culprit. Example: A buddy just getting into cigars kept telling me how he was continually having to add water to his humidifier because his hygro kept telling him it wasn't humid enough. He would add a bunch of water, things would be fine for a day and then bam, back to the 50's in RH. Turns out it was an analog hygro and wasn't even close to correct. Even after calibrating it refused to hold the correct humidity readings. My buddy had some awful soggy cigars for a while.:wink:
Now, if you, like most others have either already dealt with the problems inherent in analog hygros or, after reading the above are lucky enough to be skipping that step, we can move on to the next major category of hygros: DIGITAL.
Digital Hygros come in an astounding number of shapes, sizes and functions, so I will break them into three basic categories: Basic, Adjustable and Wireless. As to downsides for digitals, obviously you will need to replace batteries now and then.
Basic Digital Hygrometer:
The above is a perfect example of your basic digital hygrometer. It is a Western Caliber 3 and has a reputation for being a reliable and accurate hygro. It shows temps in C and F as well as RH rounded to the whole number. Some Digitals will show you the RH to the tenth as well as whole numbers, but really it isn't necessary. This particular digital happens to be rectangular. You can find them square, round and just about every other shape out there. They can be had thick or thin, small or large, and even, in the case of the Little Havana Perfecto Hygro, in the shape of a cigar. Many come with magnetic or sticky backing so that they can be attached to lids of humidors and some are even designed to fit humidors with built in hygrometer frames. If you plan on attaching a hygro to the lid of your humidor, make sure to pay attention to the measurements to assure there is enough clearance between the lid and your cigars. They all perform the same basic function and are more or less reliable and accurate.
All have a certain measure of accuracy, usually in the +/-1% or 3% range. Regardless of what is advertised, you will need to calibrate, note the amount the hygro is off + or - and add or subtract that number from the reading on the hygro to get the true reading. I tend to stick a piece of masking tape on the hygro with this notation so that I don't have to go searching for notes. I recomend doing this at least once a year (every 6 months is better) as even digital hygros can change readings over time.
ADJUSTABLE Hygrometers
For those of you who simply HATE looking at a hygrometer and having to subtract or add to get to the real reading, this is right up your alley. The above picture is of the first group of adjustable hygro's to come out. Xikar now has their own versions out. I have not used them, but Xikar puts out good produts over all and I'm sure these are no different. And a I have to admit that their version of the rectuangular hygrometer is pretty sharp. I have multiples of the above original hygrometers and absolutely love how they work. Simply calibrate to test the reading on the hygro and note the difference + or -. Remove the hygro from the container/bag, turn the adjustment knob the number of clicks needed to correct the reading (one click clockwise to add 1% to the reading or one click counterclockwise to subtract 1% from the reading) and press the "set" button. After a second or two, the lcd will reset and your reading should be corrected. I have never used the Xikar adjustables, but it sounds as if you simply push and hold a button for 5 seconds and the hygrometer sets itself at 75% RH. While this is easier in one sense, it means that you MUST have the Boveda one-step calibration kit. For the others, you can use any of the Boveda packs in any RH and adjust the hygrometer so that it reads corectly.
I recommend placing the hygro back in your calibration setup after this to confirm the correct adjustment has taken. If you are going to go the extra mile to get an adjustable hygro, it only makes sense to make sure it is right on the money.
There is a magnetic attachment on both the round and rectangular versions (at least the originals, not sure about Xikar) that will allow you to attach these to your humidor if you wish.
I only have one complaint, and that is that they aren't...
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