Light measurements and ideal ranges

BCbudinTO · Post by **BCbudinTO** » Wed Aug 17, 2016 5:35 pm

Hi,

Just wanted to start a thread for discussion of the topic of light measurements and opinions on ideal ranges. I'm setting up a small room and I'm trying to figure out how to build it "ideal" for lighting and cooling. I was hoping to get a few different opinions because the more I read the more I find it ends up with a bigger "well, it depends..." I've always grown using watts as my guide and aimed for a 50-70 watts per square foot ideal. But now I'm talking to people and they're all about PAR as a standard for measuring light. I also find that when I ask about ideal ranges for PAR it results in a nerdgasm soapbox in which I get lectured "PAR is just a measurement of..." with a number of technical sounding acronyms and "dependent on" phrases in which they basically say "all lights are different and so you need to know about their individual spectrum of output" etc etc.

Should I just stick with watts/sq foot?

MadMoonMan · Post by **MadMoonMan** » Wed Aug 17, 2016 6:34 pm

Im testing out some T5 HO 4 foot now for sprouting and vegetation. See how far it goes. Just moved cup sized transplants into 5 gallon buckets.

My primary reason to test this out is to save money on the early growth with lower cooling bills.

Post by **Jesús Malverde** » Wed Aug 17, 2016 10:58 pm

As long as the lighting type is familiar to you, might as well stick with units and measures familiar to you as well. If you aren't using lighting that's markedly different to what you are accustomed to, just go with what you know. A lot of people geek out on tech and it's 90% *wank gesture* just to show off or snob out on other people. If you are using HID and HPS lamps, why try to reinvent the wheel?

MadMoonMan · Post by **MadMoonMan** » Sun Aug 21, 2016 7:31 pm

for me ... I hate air conditioning and don't use it. reason I grow indoor in late fall normally.This year I'm starting a little earlier to get a jump start on legislation. I may be crazy but I usually have a reasoning for something.

Eventual move will be to HPS and other long term plans.

Back to how close lights should be.

Unless your a Master engineering student doing a thesis. Use the back of your hand or your wrist pulse area like the temp for a babies bottle.

What amazes me is how the large industrial grows hang those lights so high but I guess with more lights the waves all interact and mix and do photon sex things with each other so 2 waves inteacting kinda is better than to individual photons firing around bouncing of things and ricchocheting around crazily.

MadMoonMan · Post by **MadMoonMan** » Sun Aug 21, 2016 7:54 pm

I hate photons grr. You know they are why your aging and dieing and geting cancer and anal probes from demented scientists>

They are passing through you right now. Fortunately they are so small most just pass on through on their journey to the end of the universe. OOps Brain alert Section 8190000terrascecter 388888 4.222 8 just recieved a 2nd hit since birth. cell withers and dies.

Now thats some really disatant light that just kill a part of you. Wear all the aluminum you want thats just one way your dieing by things you need to stay alive.

Your breathing? Whats that your breathing? Oxygen? Oxydizer.

Water? your drinking some water right?

Stop drinking water and breathing oxygen and move into the center of the earth in a lead cave and you will live longer.

"What can I do? To change the world."

I'm glad you asked.

Become a vegan and only eat non sentient plants.

Prawn Connery · Post by **Prawn Connery** » Tue Aug 23, 2016 4:45 am

BCbudinTO wrote:Should I just stick with watts/sq foot?

Yes.

Unless you are growing with LEDs.

And even then, the answer is still yes. LEDs just need fewer watts per square foot because they don't waste as much energy on heat and other forms of radiation that plants can't use to synthesize.

Which begs the question: how efficient are HPS lamps with reflectors?

The answer is: not very.

But if you're going to use them, then 70 watts per square foot is a good guide.

MadMoonMan · Post by **MadMoonMan** » Tue Aug 23, 2016 10:08 pm

Don't mind me. I've been testing out lots of lights over the years. I had a house which had been an office and had a basement with flourescent ceilings. My first room grow. Before the internet. We only had Ed Rosenthals book and 1 or 2 others.

I couldn't at the time take the ceiling lights out so I built cabinets and ladders and boards together to raise the plants up to the ceiling .... .

MadMoonMan · Post by **MadMoonMan** » Tue Aug 23, 2016 10:31 pm

t5 Ho's

MadMoonMan · Post by **MadMoonMan** » Tue Aug 23, 2016 10:40 pm

This was about August 15? when I transplanted from seedling cups into 5 gallon pots. Once they rooted in they started growing pretty fast.

MadMoonMan · Post by **MadMoonMan** » Tue Aug 23, 2016 10:59 pm

Like I said this is experimental and is expanding. As long as there are light particles floating around we will endeavor to persevere! This was week or so ago. Haven't changed any light heights yet.

Some higher than others is on purpose. See, this is Science man.... You don't go messin' around with science and stuff so you have to do controls. Duh.. You really thing I'd be so stupid as to hang my lights unpurposefully at uneven levels? Well... I have a plan so what have you got? 8 eggs in the frig and Dachsund shit in your back yard? Well. Whos better off here now I ask you?