How far away are you using them. Each meter is different and requires a certain distance. Try the inkbird at 12-14 inches on multiple leaves. Lots of times its just the difference in the tools… I wouldn’t trust the fluke with that reading. In seeing aome heat stress but not at the level that would coincide with 85f leaf temps… 78-79 seems about right for the signs im seeing cause its not bad but nonetheless its thereYou can't measure leaf temps accurately now days with all the China junk IR's out there. Just measured them with a now $500 Fluke and a $35 Inkbird. China junk Inkbird has them on ave. 4F above ambient and the Fluke has them 2F below ambient. I'm done with leaf temps,,, those days are over for me. And my Fluke is so old they don't want to work on it anymore or calibrate. And it's $500 to replace it. While it's still accurate when it was calibrated 2 years ago the switch and power drain is horrible. The gun safe door is always at ambient air temp. Fluke shows 72F which is correct and the crappy China junk shows 78F. There are no issues with transpiration. Everything is fine. The plants foliage feed fantastic,,,, nothing is going to change in my grows concerning this topic.