Best way to measure temperature?

[Kyle1116]

What's the best method to measure temperature? A indoor/outdoor thermometer or a hand held temp gun? My thermometer says it's 75 but the temp gun says the tops are at 68? I'm confused

 

[Newf]

Your leaves may actually be cooler than the surrounding air due to evaporation of water from the plant leaf. The room air temp may be 75 but the leaf may be 68. Does the temp gun measure any other solid object nearby at 68? (The pot and dirt may also have some lower temp due to evaporation and shade so I would not compare those either.)

 

[Newf]

Also, even if the temp gun is more accurate in some ways I would still go with the thermometer since that appears to be what most other growers use and what is referenced on the web site and forums.

 

[Insight]

I get almost the same numbers as you. (with the lights off). The indoor/outdoor thermometer is measuring the ambient air temperature of the tent. The gun is measuring the temperature of the leaf. I can see how they might be different...the plant is cooling itself through transpiration, and other biological processes are occurring. My thermometer and gun correlate well to each other.

I'll have to check the temperatures with the lights on also....I wonder if the absolute difference (air vs leaf) will be different.

 

[Kyle1116]

My dirt is measuring about 63 degrees...is this a problem?

 

[Kyle1116]

No Title

 

[9fingerleafs]

I agree. Air conducts heat very fast and solids not so much so the air will always be hotter. About the gun. Try putting some blue tape squares around different surfaces to get more accurate readings. So the reflectivity won't interfer with the gun. Your main concern should be the temps of the air around the roots and the pot itself. So I would leave he thermometer ground level next to the pot

 

[Kyle1116]

9fingerleafs is 63 degrees too cold?

 

[9fingerleafs]

during the night time? its ok, you going to get every purple trait avilable, if that's the temp during the light cycle then i recommend check the soil temp a few minutes before the lights go on, this is the coldest time, i think around 50 degress and bellow it can become a problem and most processes stop but many people has freezing temps and they seem to manage even outdoors.