Intensifying light by isolating and reflecting

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dragon49

You can get a pretty good idea of my setup from the attached picture.  I have buckets under my 4 bulb T-5.  Is it worth it for me to isolate the light by building something around the fixture and buckets, (maybe with some foil to reflect the light) so it doesn't escape?  There must be some science behind this relating to the "effective lumen output" per area.
 
 
Honestly i cannot see it being worth the trouble, that and airflow would be reduced leading to other problems.
 
Remember, flat white paint will reflect more light than aluminium foil and also that foil can focus light on one spot (think magnifying glass) and damage leaves. I can't see that happening with cfl's but it's something to keep in the back of your noggin!
 
At the moment your plants are at a very young stage (small), that being said the leaves arent in need of the extra light afforded by reflection. Once your plants get larger and have more foliage the need could possibly arise for side reflection to get light reflected back to your lower leaves.
I have to agree as well that could cause circulation issues to start enclosing panels to reflect light. One of the things with using standard floro and cfl is their usable light range is relatively short due to being less intense than a HID or LED, so to get good reflection the panels would in essense have to "crowd" your plants and thier air space. If you were to use LEDs or HID the refecting panels would help with efficiently reflecting the light as the panels wouldnt need to be as close to the plants thus not affecting air circulation as much.
So, not yet, :)
 
Thanks for the replies.
 
I grew indoors last year with the same setup (+ a single bulb T-5 @ 5,000 more lumens hitting it from the side (- I'll have this later on in this grow) making the total lumens = 25,000 ) and was able to get large plants with tons of leaves and flowers and some pods, but much fewer pods than I expected.  I'm worried that the lack of production was due to a lack of light (Maybe I barely have enough lumens to get peppers) and want to maximize my output.  I'm still learning about growing and suspect that pod production may require more light than the other stages of development.
 
I appreciate the advice regarding restricting airflow and possibly burning leaves.  I also need to worry about heat and fire hazards.  Now, I am very comfortable with the "cool" setup, but suspect that enclosing the setup can greatly increase the temperature of the immediate area.
 
You will struggle to get decent harvests with just cfl's. Well from what i have seen anyway.
 
I'm sure some nerds out there do it just fine!
 
I can see it now - drago wins prize for being first grower to induce sun scald via artificial light…..  ;)
 
Garretts Bitch said:
You will struggle to get decent harvests with just cfl's. Well from what i have seen anyway.
 
I'm sure some nerds out there do it just fine!
Click to expand...
These are 4 foot tube florescent lights, so they are fl's not cfl's, since they are not compact.
 
I'm a nerd and I'm proud of it!

geeme said:
I can see it now - drago wins prize for being first grower to induce sun scald via artificial light…..  ;)
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What prize do I get?  I've already scalded plants by putting the light too close to the top leaves.
 
Well, I would say you could come to Cleveland and root for me in my next swim meet, but apparently someone thought that coming here after contracting Ebola was a good idea, so maybe not. 
 
Hey dragon49, how about doubling up on what you did last year and get more side-lighting?
As for a reflective enclosure--if you can afford it, why not? Every little bit helps after all.
Think about lasers--take a tiny light source and you reflect it into just one direction, you end up with some pretty intense light.
And if you're T5x4 didn't have a reflective hood, you'd already be wasting 50% of your output.
 
Guess you'd need to build in some fans or something for air circulation though.
 
Garretts Bitch said:
Remember, flat white paint will reflect more light than aluminium foil and also that foil can focus light on one spot (think magnifying glass) and damage leaves.
Click to expand...
 
Where did you get the idea that flat white paint reflects more?  Many people who have tested this found the opposite to be true.   Yes you could fashion some kind of parabola out of foil that intensified the light, but you'd almost have to try to do that to have it too intense.
 
Looking at the picture, I'd estimate that less than 5% of the light is falling on the plants.  It's a bit harder to control spillage with 5 gallon buckets but it could be drastically reduced with reflective panels around the 4 sides, draped over the top of the fixture, and cutouts in the middle for the plants with a few inches to spare.  It still wouldn't be remotely close to 100% effective light but let's say it might double or triple it for the cost of a few metalized mylar emergency blankets and a few pieces of cardboard box backing if needed, about $5 total cost to increase light output that much is not bad at all.
 
Airflow will be fine with a modest fan bringing in a volume of outside air sufficient to keep the temperature at a good level, below about 90F.  That may mean only part of the air is pulled in from outside and the rest is recirculated interior air.  Fan placement can be adjusted to reach a good temperature.
 
Would you mind posting the results then?
 
 
Reflective Chart

Material Percent Reflected
Foylon 94-95
Reflective Mylar 90-95
Flat white paint 85-93
Semi gloss white 75-80
Flat yellow 70-80
Aluminum foil 70-75
Black less than 10
 
I wouldn't buy any of Cervantes books at gun point, but this is a decent reference.
 
Mylar emergency blankets are terrible. They're too thin, creased, allow light to pass through, and wear out like cheap underwear. If you're going to use mylar, buy the thicker 2-10mil material and laminate it to a flat surface.
 
Flat white paint is durable, easy to clean, highly reflective, and in contrast to mylar or it's bastard cousin, aluminum foil, provides diffused light.
 
But this is all for naught, because it's just a bloody pepper plant :P Every single aspect of a grow doesn't have to be the best, use what you have, or don't. A loss of a bit of light and yield = meh.
 
I'm not going to bother to try and make the current setup more efficient.  I decided on MORE LUMENS!  I just purchased six 2,800 lumen CFLs ( http://www.homedepot.com/p/EcoSmart...-CFL-Light-Bulb-1-Pack-E-ES5M842/202067799%C2 The site says 2,900 lumens but the package says 2,800.  These are 2,700K, not the current 6,400 (Daylight) K that I currently give the plants.  Hopefully this will not be an issue.  Depending on opinions, these are either better for flowering, or the spectrum doesn't really matter.  I need to rig up something to get these to hit the side and bottom of the plants.
 
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