Just curious if anyone of you have them and your thoughts on them?
Is it basically just an ir thermometer? Is this a tool that can really make a difference or are you good if you’re monitoring your temps and humidity?
I have not had any experience with these, just curious about your all thoughts is all.
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It could be useful; however, I don’t know many growers who expend a lot of effort on chasing VPD. Given that, it seems unlikely that a perfect VPD leads to significant improvement.
I expect what the device does is control for either or both temp and RH by making the necessary adjustments to temp and/or RH to maintain the proper VPD. It would execute functions to adjust temp or RH based on VPD high/low setpoints.
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When I first started I chased VPD. It was a hassle. I don’t bother anymore and I do get decent results.
That said, I would guess that the AC infinity device functions and does the job that it is supposed to.
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Me either. I keep it simple and just shoot for ~60% in veg and 40% in flower.
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Same for me
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Me three. Gave chasing that up a few years ago 
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It’s basically just an IR gun. I have a couple, one for working on engines (Fluke $$$) and one for finding the hot spots on my griddle & grill. (amazon special)
Finding emissivity for organic matter is a bit of a pain, I just use the setting for wood. Off the top of my head I wanna say .93… but I’m not sure.
I do want to try letting the controller 69 pro do it’s thing, but for now I’m doing just like the guys above, starting around 60% slowly dropping to low 40% during flowering.
It may have settings specific for leaves, but it’s double my amazon special that I already have.
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I just have never seen one. Someone in a Facebook group posted that they got one. I thought it looked like the ir gun we use at work to check temps and thought I’d ask.
I think I’ll save the $30 this time around. 
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A growmie friend has the whole AC Ifinity top cintroller that runs his occolators, intake, exhust fans as well as turns his lights and air conditioner on and off and run the T3 humidifer. Set up for 2 weeks so far and he loves it.
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Ive got the whole ACI setup minus the IR thermometer and I love it too, on my second grow. VPD is important but it goes hand in hand with ppfd, dli, ventiation, ph,etc. You really have to have to whole package to benefit the most. Knowledge is key the, never stop learning.
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I believe the thermometer would be redundant with the controller giving same data. Plus with the APP that data is on your phone as well.
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You want to know the leaf temperature in addition to the surrounding air temp & RH, in order to calculate leaf vpd. The leaf temperature offset distinguishes leaf vpd from air vpd. Although if it’s zero, then they are the same vpd number. Otherwise, they are different.
Leaf Temp - Air Temp = Leaf Temperature Offset
Some controllers let you plug in the offset so that it isn’t zero & just giving you room/air vpd. Having the ir sensor built in & always watching & adjusting seems like it would make a lot more sense.
If you don’t have a controller & are using static charts & air temp & RH sensors, & an ir gun for the leaves, then the leaf temperature offset is also the difference between different static vpd charts, so you want to match the offset of the chart to your actual offset.
Keep in mind that vpd targets are leaf vpd targets, not air vpd targets.
Practically I think it might be a more useful approach to take the ir gun & try to go after an ideal leaf temperature range, & to chase vpd targets is tough, but if you run the real numbers & know you aren’t off on the wrong chart, or tuning air vpd towards leaf vpd targets or whatever, then at least you know your real leaf vpd numbers, & your leaf temps. Also it can be useful to watch the offset for changes.
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I just guessed lol. I read the average LTO is -2 with led lights. Seems to work fine.
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Just talked to my buddy and yes the ACI 69pro does have inputs for the LDO in its set up program. How much it adjusts the environmental controls not sure but it definitely takes it into consideration. He just notified me he is gifting me a 69 pro next week (he ended up with an extra) so ill be experimenting with it this grow im about to start.
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I have the offset programmed in mine just to monitor. I just have the lights and fans in “auto” mode, with temp and humidity as triggers, with buffers, and it stays right on the high edge of good in the vpd charts.
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The 69pro is able to control VDP to within decimal points automatically once programed with a start and end point as it runs thier exhust and intake fans,lights (on /off), humidifiers or dehumidifiers and even Air Condition system, to attain and maintain VDP by itself.
If you ain’t testin’, you just guessin’. You might be close, though. It would be way off for my setup. Well, that would be close to my lights-out offset. Lights-on & I usually see -8 to -10 f leaf temp offsets, unless they get stressed, & then it will usually tighten up.
It’s only as accurate as the leaf temperature offset that you plug into it, compared to what your actual offset is. Leave it at zero & it’s just telling you air vpd. Move it farther away from where it actually is, & the accuracy gets worse & worse.
It would use it to decide what/how much to adjust anything, if at all. Still up to you to calculate & plug in your actual offset. Then you have to worry about it changing. After a while you’ll know how your plant runs if you test manually, or you could let the ir sensor do its thing. But I wonder if the controller provides for a lights-out override, or if it would still just mill away towards lights-on targets in the dark, or what.
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From my understanding it monitors 24/7 and adjusts on the fly as the enviroment changes (light on or off) humidity up or down ect.
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It takes a lot of work and time out of the process for sure.
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Seems like it takes care of a piece of the puzzle. One more i dont have to…
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