Reflector / hood test

[o2much4me]

Reflector efficiency - the total amount of light the reflector puts on a 4'x4' area using a 1000 watt hps bulb, measured at 25 spots (5x5 grid) with the reflector 24" above the surface. Reflector value - efficiency divided by price (bigger numbers are better). We did this testing to answer your questions, provide the best grow light packages, provide accurate recommendations, and save you money by cutting through the hype and letting you pay for performance, not marketing.


test.htmlhttp://www.greners.com/reflector-test.html

 

[332359]

Reflector efficiency - the total amount of light the reflector puts on a 4'x4' area using a 1000 watt hps bulb, measured at 25 spots (5x5 grid) with the reflector 24" above the surface. Reflector value - efficiency divided by price (bigger numbers are better). We did this testing to answer your questions, provide the best grow light packages, provide accurate recommendations, and save you money by cutting through the hype and letting you pay for performance, not marketing.


test.htmlhttp://www.greners.com/reflector-test.html

Your not going to have accurate peak data with the way that you did your tests. I do these tests also but you missed something. The lights should not be hung 24" away from the grid. I make sure that I hang the reflector much lower than 24". Then I raise the reflector until the 4 corners on the grid get to the highest numbers possible. Then I adjust the reflector to make sure the 4 corners read the same but if I lower it, the numbers on the meter go down as well as if I raise it the numbers go down too. That is the sweet spot that the reflector should be hung. The light on the corners of the grid will be at the highest light possible. I noticed from these tests that reflectors that are wider should be hung lower than reflectors that are small. Some reflectors that I tested needed to be hung at 17" with 1000 Watt HPS. It just so happens that my more condensed reflector has its peak output at 24". Once you test this way, you can record the data and know how high each different reflector should be hung. I recorded all my data.

 

[dansbuds]

cool ..... my blockbuster 6's are in the top 3 !!!

 

[yerboyblue]

Did you test any Sunlight Supply Cool Suns? They are similar to DansBuds blockbusters but the ends are vertical instead of slanted.

edit: Nevermind, you got a few in there that are similar to what I'm asking.

 

[Cali MedPatient]

Your not going to have accurate peak data with the way that you did your tests. I do these tests also but you missed something. The lights should not be hung 24" away from the grid. I make sure that I hang the reflector much lower than 24". Then I raise the reflector until the 4 corners on the grid get to the highest numbers possible. Then I adjust the reflector to make sure the 4 corners read the same but if I lower it, the numbers on the meter go down as well as if I raise it the numbers go down too. That is the sweet spot that the reflector should be hung. The light on the corners of the grid will be at the highest light possible. I noticed from these tests that reflectors that are wider should be hung lower than reflectors that are small. Some reflectors that I tested needed to be hung at 17" with 1000 Watt HPS. It just so happens that my more condensed reflector has its peak output at 24". Once you test this way, you can record the data and know how high each different reflector should be hung. I recorded all my data.

Cool Dumbledore, where can we find your data?

 

[emeraldfarmer]

Great info but does not really talk about the light pattern and penetration. Which hood would be best for a table?

 

[332359]

Cool Dumbledore, where can we find your data?

I will eventually post it up. All my computers and files are in storage for security reasons. Ill get to it as soon as I can. What I did learn from the tests is that the bigger bulkier reflectors needed to be hung much lower and average around 19" or you would lose major output. I remember seeing a 25% loss of light on some bigger reflectors if you hung them at 24" and they needed to be hung much lower to get a similar output of a smaller reflector. The other problem that I saw with the bigger reflectors is that if you want to get the maximum output compared to the good smaller ones, they have to be mounted much lower which puts too much heat over the plants and need to be air cooled. Other smaler reflectors that I tested didn't have to be air cooled because they were so high. I did not test every reflector on the market but I do plan on it. I was very anal with my tests and I did not draw or tape a grid onto the floor. I made a grid out of plywood with 25 data points. I leveled the reflector and to make it perfect I moved the plywood because I would have to unscrew the reflector if my grid didn't move. This is because every reflector doest get hung in the same position as others. They may have to be moved an inch. Some more. Its not all about centering your reflector to the grid because its all about the design of the reflector itself. Not all ends on reflectors are the same angles. This is why the 4 corners in the test are important. Its kind of like calibrating your grid so you obtain accurate data. And I haven't even talked about light penetration within the canopy yet. There's a lot more variables to these tests that people miss.

I have been collecting data for many years on many aspects of growing. I've learned many things from data and knowing my variables. I didn't collect data of a room. I collected data of my friends grows too and provided collecting charts for them to make it an easy task. One day I will be posting up all that data.

 

[o2much4me]

Your not going to have accurate peak data with the way that you did your tests. I do these tests also but you missed something. The lights should not be hung 24" away from the grid. I make sure that I hang the reflector much lower than 24". Then I raise the reflector until the 4 corners on the grid get to the highest numbers possible. Then I adjust the reflector to make sure the 4 corners read the same but if I lower it, the numbers on the meter go down as well as if I raise it the numbers go down too. That is the sweet spot that the reflector should be hung. The light on the corners of the grid will be at the highest light possible. I noticed from these tests that reflectors that are wider should be hung lower than reflectors that are small. Some reflectors that I tested needed to be hung at 17" with 1000 Watt HPS. It just so happens that my more condensed reflector has its peak output at 24". Once you test this way, you can record the data and know how high each different reflector should be hung. I recorded all my data.

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You have a good point. I cannot claim I did the test but I did think it would give a reference point.

 

[the gnome]

I'd like to see the stats on the 4ft parabolics....

 

[Hydro-Soil]

Great info but does not really talk about the light pattern and penetration. Which hood would be best for a table?

Looks like the raptor 8" has the most even spread... going from the nearly equal perimeter and center averages.

At least when it's 24" away.... that is.

Stay Safe!