Transpiration cools leaf surfaces, so the actual leaf temp is typically less than tent air temp. I've been curious about how much less. There are 5 cheap RH/temp meters placed around the tent near the canopy surface, along with Nano. An infrared gun thermometer was used to measure leaf temperatures. The 5 RH/Temp readings were averaged to get single values, and 4 IR thermometer readings were also averaged. For a total of 33 trials (9 measurements each trial), spread over 5 days, the leaf temp appears to be 7 F lower than the ambient air temp. I saw that many people were assuming 5 F in a few internet posts. This has important implications for VPD calculation. The tent has averaged about 80 F air temp and 60% RH, yielding a VPD of around 1.4 kPa, which is outside the approximate recommended range of 0.4 to 1.2. If the 7 F cooler leaf temp is used instead, then the VPD is 1.1, within the recommended range. Being able to set Nano's temp/RH values to match tent values would be very useful.