Light intensity conversion

[aclum]

Hi,

I was reading an article about lighting seedings after grafting and there were references to mols or mini-mols (???). I can't do the symbols on the keyboard exactly but it starts with sort of a "u" with a leg down on the first upright of the letter and goes sort of like this:

umol/m squared/s

I'm sure anyone who might be able to answer my question knows what I'm talking about

Can anyone tell me what the equivalent to 250 and to 135 of these units would be in fluorescent light wattage and distance from seedlings? I'm currently using t-5 lighting but have t-8 and t-12 available.

Thanks!
Anne

[Worth1]

Originally Posted by aclum

Hi,

I was reading an article about lighting seedings after grafting and there were references to mols or mini-mols (???). I can't do the symbols on the keyboard exactly but it starts with sort of a "u" with a leg down on the first upright of the letter and goes sort of like this:

umol/m squared/s

I'm sure anyone who might be able to answer my question knows what I'm talking about

Can anyone tell me what the equivalent to 250 and to 135 of these units would be in fluorescent light wattage and distance from seedlings? I'm currently using t-5 lighting but have t-8 and t-12 available.

Thanks!
Anne

Anne what exactly are you trying to do and or worried about.

Worth

[aclum]

Hi Worth,

Thanks for your post! Always happy to see someone respond

I wouldn't exactly say that I'm 'worried about" it, but an article (I'd linked to in an earlier post) on the effect of light levels on the healing rate and survival of grafts:

http://www.vegetablegrafting.org/wp/...ter-dec-14.pdf

uses light levels of 135 and 250 micromoles in their experiments. I just wanted to know the equivalent in terms I'd understand in case I wanted to recreate those conditions.

Since I hadn't got an "easy answer" from my post, I did a little more research and found this great site:

http://www.egc.com/useful_info_lighting.php

where one can convert micromoles (photons equivalents) to other measures including LUX - among other things. I should be able to measure LUX over my plants with a smartphone light meter app. I can probably also convert things using the lumens and/or wattage of my T5 HO bulbs.

BTW, haven't followed all of it yet - but I might pop into your fermentation thread one of these days. I have passing interest in fermentation (kefir, sauerkraut, sourdough bread, etc.) and highly recommend the book 'The Art of Fermentation" by Sandor Katz (if someone hasn't already mentioned it in your thread).

Anne

[aclum]

Hi Again,

Not sure if anyone's following this, but just to finish what I started.......

As per this post from another website:

http://www.orchidboard.com/community...longevity.html

each of my 2' 24W T5 HO blubs puts out 58 micromoles/meter squared/second at 1' above the plants so my fixture of 4 bulbs would put out 232. Using the inverse square formula (as noted in the linked post) I can raise or lower my fixture to achieve the 135 and 250 micromoles/meter squared/second lighting levels noted in the article on the effects of lighting in healing and survival rate of grafts.

Whew! Now I can rest easy

Anne

[Worth1]

I'm following it.
I did a bunch of research on lighting a while back and ended up with my own Sun in the house.

Worked great I didn't have to keep the lights near as low as usual.
I used 12 equivalent 100 watt CFL lights in a 3 X 4 area.

Worth

[aclum]

W.





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