It is a selling point because the environment created and maintained is what matters… your 1 ml comment doesn’t really apply… especially when it doesn’t really change anything… yet in curing it does make a difference being pinpoint accurate. Without fluctuations
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Yeah, its too small. Yet it manages to stick out from wall too far. Its deeper than the mini-fridge that was in its spot prior. I would prefer a bit wider with less depth. Awkward dimensions. Is what it is.
I agree, for what it is, the selling price is too high. Again, is what it is.
Until the market has alternatives, it is what it is.
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I think what’s most important here is empirical data. If the device works for you and you’re happy with it, that’s really all that counts.
I would like to dispel a couple of myths here, though. Just because the digital display is showing measurement accuracies of 0.1° and 0.1% does not mean that is what they are controlling them down to. Most temp sensors are capable of reading down to 0.1° of accuracy, but there are many factors that can and do affect that. Most humidity sensors have an accuracy of +/-5% over the range. You have to have hysteresis built into either the circuit or the code. In this case, I can almost guarantee it’s in the code. If you didn’t have hysteresis built into your home furnace it would cycle on and off endlessly trying to maintain a temperature setting within 0.1°. Hysteresis is the “window” between the set point and the actual. Add to that the moving air from the fan and it complicates the measurements even more. The most common techniques are averaging the readings and only checking them periodically. If you try to hold a tight PID loop with temp and humidity, it just fluctuates all over the place.
Anything you would like to add here @FieldEffect ?
As for the cost, that’s just supply and demand.
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Hello all glad to see this thread is still going strong. I had to stop growing late last year and have a couple medical issues that now are in control and soon as I can get my neck fused again I wont be on any meds other that blood pressure which no biggie. Some of the other stuff like blood thinners have side effects that I would not want to live with long term but in a couple months or so all should be good.
Anyway nice to see the unconvinced and skeptics keep showing up, a few take a chance and buy one and are new members of the faith and a few keep trying work arounds that just are not the same. There was one particular screaming baby in the first dozen pages that finally left but said he would be back with his home built that would work just as well. Seems nowhere to be seen 
I am getting ready to restart my garden and have a second year gift of a MAC1 from the man himself over at the BeanBasement on the way anyday. Plus a couple other things maybe but MAC1 hits our sweet spot so Im not all about growing a half dozen things at this point. Still have a grove bag full of Blue Dream and MAC1 but wife still prefers MAC1 best. Good to see the setpoints are pretty close to stock but I may follow Jets setting but I am a few months out from that.
Good luck to all those who bit the bullet and invested in the Cannatrol. I am glad I did.
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For those of you with a freeze drier + cannatrol is there a difference when you freeze dry first and then toss into the cannatrol or would you be better off skipping the freeze drier?
I know most of the freeze dried buds I’ve seen has had like what happens in a crop circle… all the trichomes are laid down like a strong wind blew them all over… seems destructive
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That’s totally true. Typically the control loop operation range will be a few times the measurement resolution. Sometimes, this is hidden to the user. They may have 0.01° internal measurements and only display to the user the truncated/rounded 0.1° figure. Whether dew point or temperature.
As a general note absolute accuracy better than 0.2°C and +/-2% RH are inexpensive to come by these days (I use an SHT31 in my dry cabinet). Note that the resolution of that sensor is 0.01% and 0.01C. Resolution/precision are different than accuracy. Better than 1.5% RH absolute accuracy is difficult to come by, even with industrial precision instrumentation. Most dew point sensors offer approximately a 0.1°C dewpoint resolution, which equates to about 0.2% RH at the absolute humidities in question with this discussion (the implication being that holding a dewpoint within 0.1°C [0.2°F] means the humidity is only known within 0.2%). All these metrics are related to each other. The key takeaway is that accuracy less than 2% RH is very difficult to achieve and maintain.
And, FWIW I spent two summers building something very similar to the Cannatrol. It’s ugly and took quite a bit of time investment. It works great and does a few pounds at a time. But it’s not intended to BE a Cannatrol, it’s an independent experiment aimed at getting the best dried cannabis I can. I settled on a different control mechanism than dew point (vapor pressure differential) which is the primary evaporation “throttle pedal.” In the end I control for a fixed water activity level. BUT: I have different constraints, level of knowledge, technical capability and interest than the average person buying a Cannatrol. I’m happy they [Cannatrol] have carved themselves out a niche in a market to make a good living. I’m glad folks are getting better weed than they previously did. I don’t frequent this discussion because I don’t, and probably won’t, own a Cannatrol and seldom can add anything of value.
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We are getting lost in the trees again… I think my point was and still is… the fluctuations are next to nothing… despite an allowance of error or inaccuracy… nevertheless quickly keeps it right where it has been set… I mean within seconds of opening the door… i still will disagree that anyone built anything similar… will what u built dry weed… I’m sure it will … but will it cure weed at 70 watts?? I think not
Also I can keep this thing curing for 99 days… etc… very low cost to run indefinitely
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I’m truly not trying to derail the thread. Everyone that owns one seems very happy with it and I think that’s really all that counts.
The point I’m trying to make is that visually, you’re not seeing fluctuations because they are being averaged out and sampled at a rate that makes the unit appear more stable than it actually is. You cannot get that type of resolution with a sponge and a fan. This is what you would normally pay for a unit with that type of accuracy:
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did you leave the dry at 53.5?or default 54?
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16k? That’s a nice used car. 
The point I am making… is that when I do see a fluctuation… like when opening the door for a good 30 seconds… after closing, quickly… within another 30 seconds is back to the setpoint… whether or not the degree of error is in full swing or not… doesn’t matter… everything has this degree of error… everyone’s dyi cure dry room has a degree of error and allowance for that… it’s the technology in this machine that makes it so nice… it does what the claims say it does… so with that… whether speculated on in 10000 different tiny aspects or not by whoever… means nothing more than some words out on a screen… especially when this machine does such a nice job drying and curing… I’d love to see someone create a dry/cure room that will ramp from beginning settings to ending settings perfectly like the cannatrol does… it’s superior hands down… sorry to anyone who refuses to believe that… props to all who stuck their neck and cash on the line because in the end… it’s worth it
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What made my mind in the beginning was… imagining an entire crop being trashed in the garbage over mildew or moldy buds because it can and does happen… count me out on that moldy weed lol
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I’m not trying to argue with you, and nowhere did I say it’s not worth the money. I don’t understand why you’re getting so defensive. I think for the cost it’s a decent unit and everyone that has one seems to be happy with it.
I can write code right now that will display the temp and humidity that matches your setpoint if the true reading is within +/- 10, 20 30 or 100% of it. It’s that simple. Just for giggles, grab a handful of the Amazon temp/humidity sensors that we all have a bunch of and throw them in there just to see what they display. Or buy a good one and check it with that.
All I’m saying is don’t take anyone’s word for it just because visually, it appears to be dead nuts on. I’m not trying to discourage anyone from buying one.
Now I see why Fieldeffect didn’t want to post in here.
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Not sure where you’re getting offended. @Coda … it’s not like I am the 1 acting like I can upstage anyone with technological knowledge… (not saying you are) I just know beyond a shadow of a doubt… it does what it says… and that’s all I wanted… was for it to do what it said… yeah I’d say unless you have real input on the cannatrol you shouldn’t even be posting in here lol but hey that’s just me trying to keep the op topic on topic
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I’m not offended, bud. It’s all good 
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Im almost afraid to say I’m interested in buying one 
But seriously I’ve been looking into it and reading through here and it seems like it’d be a worthwhile investment for me.
I appreciate the firsthand feedback and all the science talk behind it, because this is new to me
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I don’t care what they cost. I’m going to buy another one. The headache they eliminate for me is worth way more than 1800 bucks and maybe a third just for fun. I looked into the next size unit they have and it’s 46k lol.
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The only reason I don’t have one is because I couldn’t fit one of my plants in it, let alone four. Other than that, everyone has nothing but good things to say about them.
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Yeah I’m worried I’d need more than one. Thankfully they offer bulk discounts
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