Reflectivity of sheet metal

Hi there,

I had these reflectors made for me out of sheet metal, but now after i bought them, i thought whats the light reflectivity percentage of this material? Can anyone please help me since i cannot find anything.

Thx

The best way to measure this is by using a light meter which should be available to you fairly cheap (under $30) from any grow shop in your area.

I would advise measuring your efficiency compared to results achieved by other products.

Good luck.

I have thought of a light meter, but what will i compare it to if i dont have other proper reflectors to test my specific light bulb on.
I can take the measurement without the reflector, and then with the reflector.
This will only give me 2 numbers and not the efficiency of the reflectivity of the hood.
Which is what i am looking for.

The efficiency of the hood can be compared to the advertised efficiency of others, due to the fact that you fabricated your own reflector this is the best and probably only option to get an idea of how efficient your design is.

Bare sheet metal is definitely not going to be that reflective however... I would advise you to paint it with some flat bright white paint to achieve best results for what you're working with...

ok thx.

Im not that clued up on the different paints out there, are there specific paint i need to use to paint on sheet metal, and resist the high heat? or will normal flat white paint do the job?

THanks in advance for the advicekiss-ass

K, so now i have a Sunmaster 600w MH 50k lumens and a lux meter.

If i use no reflector, should the meter read 50k lux at 1 foot from the bulb?
Now what will happen with a refelctor? Does it increase or stay the same?

I have a reflector [air cooled] painted white on the inside, at about 1 foot i measure around 80k - 90k, if i put it up against the glass i get just over 100k lux.

Does this mean my reflector is good? Or am i doin/calculating something wrong here?

Thx

I have done another experiment:

Measured Reflectivity of sheet metal with a 600w Sunmaster Cool Deluxe Conversion MH bulb 50000 lumens, then painted it white on the inside with flat white anti-rust coating and measured again..
The results where so close i can not say which one is better, [sheet metal was a small bit more reflective], i like the white paint more, and the color it gives off.

IF anyone knows of something that will increase reflectivity of sheet metal or white paint, please enlighten me.