light distance and temperature

[keepleft]

hi all

 

i have my 1000w hps lamps @ 50 cm from the plant tops (scrog method). the temperature at the plant tops is @ 30 degrees. there is no signs of light bleaching or leaf twisting from heat

 

would i be better off lifting the lights to @ 60 cm from the plant tops and therefore reducing the temp at the plant canopy to @ 28 degrees? or is it better to have the lamps as close as possible for maximum light penetration - despite an increase in temps

 

thanks

[WantDaChronic]

i think as long as there is no bleaching or heat damage, you should keep the light as close as possible to ensure your plants are getting all the light they can :smoke

[naturalmystic]

With a 1000watter 10 cms shouldnt diminish lux over plants and they may be happier ?

[WantDaChronic]

With a 1000watter 10 cms shouldnt diminish lux over plants and they may be happier ?

<{POST_SNAPBACK}>

 

i think 10cm might be a bit intense, but if you have an air cooled hood and fans to keep the temps down, it shouldnt be a problem :smoke

[Roadblock]

Hi

 

I personally would move them up , I dont like them too close as some strains will run at the very tips when too close , also I want a bit of penetration that you loose because of light angles when very close , I also noticed years ago that the best buds are not always the ones closest to the bulb , that kinda got me thinking it dont have to be that extreme close , like we always say it so depends on your individual system .

 

Rod

[naturalmystic]

I meant away from the plants, the opposite of what you indicated chronic haha , yeh i thought the formula for 600 watt was 60 away from plants and a thousand watt even further away like 80 to a metre ??

[Guest Eikel]

I've tried lowering lights, and not lowering, can't see the difference personally - maybe if you were using fluros and not HIDs, but yeah I leave my lights where they sit nowadays

[Tom]

To set the light to grow height, start at a safe distance above the plants (approx 45cm for 400w, 90cm for 600w, 120cm for 1000w), hold your hand palm down level with the top of the plant for a few minutes. If it feels too hot on the back of your hand the light is too close, if cool then it's too far away. If it's pleasantly warm and it feels as if you could hold your hand there all day then it's OK.

 

[keepleft]

i thought light distance depended on temperature and that the rule was that you keep them as close as possible with temperature being the key?

 

ive had em 40cm away during the cold months of winter and the canopy temp is 28degrees. normally 60 cm in summer. but summer nights have been abit cooler this year so ive had em at 50cm.

 

but i agree with rod that the biggest buds arent necessarily directly under the light.

 

i generally go by 'leaf curl'. if the edges are curling i figure too hot.

 

what distance do you guys keep your 1000's at ???

 

ps i keep my 600's at 40cm how about you