room temp vs temp under the light?

[sunandsky]

So my room temp in the tent is good at around 75. But under the light where my top buds are is about 86. I have some ducting in there now with a carbon filter, and a 175cfm fan and the light is much cooler than it was before but still warmer than id like. Should i be concerned? I know flowering temps should be 64-78 or so but im not sure if that is just the general room temperature or what

 

[coreywebster]

Air temp is the key, which is your room temp.
Under the light the rule used to be if you could put your hand at canopy level without having to move it then its fine.
Plants can handle more radiant heat than they can high air temps.
I wouldn't worry about it.
Used to be folks would say perfect range lights on was 78-82, these days I see a lot of folks aiming for mid 70s and people saying 80 is way high, which it isn't.
Have a google on air temps versus radiant heat. Theres plenty to read on the subject.

 

[SouthCross]

Question.

How'd you measure the temperature of 86° in a space that's 75°? Are you reading the surface temp of the light surface?

 

[sunandsky]

Air temp is the key, which is your room temp.
Under the light the rule used to be if you could put your hand at canopy level without having to move it then its fine.
Plants can handle more radiant heat than they can high air temps.
I wouldn't worry about it.
Used to be folks would say perfect range lights on was 78-82, these days I see a lot of folks aiming for mid 70s and people saying 80 is way high, which it isn't.
Have a google on air temps versus radiant heat. Theres plenty to read on the subject.

alright, well i can actually place the back of my hand on the cool tube without having to move it. so then i should be plenty good i suppose, thanks man

 

[sunandsky]

Question.

How'd you measure the temperature of 86° in a space that's 75°? Are you reading the surface temp of the light surface?

i have a thermometer in there, and then another one that i hung from the ballast so that it was hanging just beside the top and closest bud to the bulb.

 

[SouthCross]

i have a thermometer in there, and then another one that i hung from the ballast so that it was hanging just beside the top and closest bud to the bulb.

Stoner moment. Just wondering.

 

[sunandsky]

Stoner moment. Just wondering.

haha no worries. i use those indoor/outdoor weather station setups. fuckin bought a new one today cause after i moved the old one wasn't reading temperatures right (or so i thought). new one said the same temp..i was like wtf is this shit man? then i realized my weather device was picking up a neighbors remote sensor. haha. waste of money. luckily it was on sale for like 75% off. calibrated it proper now and its all good, both work lol

 

[coreywebster]

Stoner moment. Just wondering.

Legit question. Its just getting heated up from the radiant energy.

@sunandsky read this
http://cannabis.com/faqs/growing/growroom-how-do-i-measure-temperature-correctly.html

 

[SouthCross]

I have four radio temp sensors. Different base stations. All over the place.

Buy a cheap laser thermometer to play around with. Actually see what the plant temp is. See how hot the light is really getting.

It's the thing checking water temps before you pour. It's $25 bucks of fun.

 

[SouthCross]

I've never checked plant temps before and the conditions here are close to your tent.

Outside air temperature is 76. 37% humidity.

Three readings off broad leaf plants in direct sunlight. Average surface temp of a leaf is 80. Highest reading was 90. Lowest 77(tree)

 

[sunandsky]

I've never checked plant temps before and the conditions here are close to your tent.

Outside air temperature is 76. 37% humidity.

Three readings off broad leaf plants in direct sunlight. Average surface temp of a leaf is 80. Highest reading was 90. Lowest 77(tree)

I actually have one of those laser thermometers somewhere. Man outside in the summer time those plants get so hot in the sunlight, its crazy. but the sunlight makes them stink so loud. but indoors I've heard, and experienced that too much heat will make them less stinky. I bought myself a carbon filter and some ona gell, have it all over the apartment, but my brother came here and said it smells really bad like pot in here. I guess iwasted all that cash for nothing. fuck.

 

[NaturalFarmer]

IR can add 5-6 degree leaf temp so depends on your light source.

 

[Jaybodankly]

I have an Infrared (IR) Temperature gun. I measure leaf temp with it.
If your temp/humidity meter is sitting where the light hits it that's room temp.
Put it in with the foliage that is leaf temp.

 

[Kingrow1]

Legit question. Its just getting heated up from the radiant energy.

@sunandsky read this
http://cannabis.com/faqs/growing/growroom-how-do-i-measure-temperature-correctly.html

Radiant heat screws my humidity meter, that never gets placed under direct light...

 

[ҖҗlegilizeitҗҖ]

I just picked up on of those infrared laser thermometers, pretty nice, I just shoot it at the tops of the plants, base of the plants, top of the tent, top of the grow room, bottom of the grow room, fanso ductwork, exhaust from tent, anything! And I can get a really great idea of what temperature everything is at and where I can improve. Right now my canopy is at 72, top of grow tent is 75, exhaust is 88, intake to tent is 68