Tomatoville® Gardening Forums - View Single Post

dcarch · January 9, 2007

Suze,

I am familiar with shrubs_n_bulbs , who is very knowledgeable in the topics of lighting, but I do disagree with him and some others in a few areas:

1. Aluminum reflects higher then 90%, that's why it’s used in almost all reflector applications, including astronomy mirrors.

2. This is an easy one: Go get yourself a piece of alum foil now and shine the brightest light you can find on it, including sunlight, you will not be able to see any light passing thru the foil. He/she is 100% wrong that 50% of the light passes thru the foil. Gold foil for artist's use yes. It's so thin you can see thru it.

3. Alum is one of the most corrosion resistant metal because it forms alum oxide immediately which protect its surface. Exterior building curtain walls last hundreds of years. It will not resist strong alkaloids very well however.

4. "Normal back-surface mirrors have a reflectivity around 90% but are not good for plant reflectors because the light is reflected "like a mirror", it will either miss your plants or hit them in a focussed way which will be damaging." is an incomplete statement and not a relevant statement most of the time. It applies mostly to a point source and poorly positioned or designed reflector. It does not apply to fluorescent lights at all.

5. White reflectors are much better then no reflectors. White, by the very definition, it reflects all colors in all directions therefore a lot of light will be lost in the directions which are not hitting your plants. The only time white reflectors are effective is when the surroundings are also all white which can reflect back the lost light. It may be misleading to perceive white to be more effective because you can see the bright white reflector and a good alum reflector appears to be very dark. The reason is that a good reflector should throw all the light where you want it to be and not on you.

With the desire to grow compact strong plants under light and with energy cost so high, it is very important to have the most efficient light source, the best focused and reflective reflector, and as much as possible a reflective environment.

I recommend the alum tape. BTW, I am not the owner of HD :wink:

dcarch

January 9, 2007	#5
dcarch Tomatovillian™ Join Date: Jun 2006 Location: NY Posts: 2,618	Suze, I am familiar with shrubs_n_bulbs , who is very knowledgeable in the topics of lighting, but I do disagree with him and some others in a few areas: 1. Aluminum reflects higher then 90%, that's why it’s used in almost all reflector applications, including astronomy mirrors. 2. This is an easy one: Go get yourself a piece of alum foil now and shine the brightest light you can find on it, including sunlight, you will not be able to see any light passing thru the foil. He/she is 100% wrong that 50% of the light passes thru the foil. Gold foil for artist's use yes. It's so thin you can see thru it. 3. Alum is one of the most corrosion resistant metal because it forms alum oxide immediately which protect its surface. Exterior building curtain walls last hundreds of years. It will not resist strong alkaloids very well however. 4. "Normal back-surface mirrors have a reflectivity around 90% but are not good for plant reflectors because the light is reflected "like a mirror", it will either miss your plants or hit them in a focussed way which will be damaging." is an incomplete statement and not a relevant statement most of the time. It applies mostly to a point source and poorly positioned or designed reflector. It does not apply to fluorescent lights at all. 5. White reflectors are much better then no reflectors. White, by the very definition, it reflects all colors in all directions therefore a lot of light will be lost in the directions which are not hitting your plants. The only time white reflectors are effective is when the surroundings are also all white which can reflect back the lost light. It may be misleading to perceive white to be more effective because you can see the bright white reflector and a good alum reflector appears to be very dark. The reason is that a good reflector should throw all the light where you want it to be and not on you. With the desire to grow compact strong plants under light and with energy cost so high, it is very important to have the most efficient light source, the best focused and reflective reflector, and as much as possible a reflective environment. I recommend the alum tape. BTW, I am not the owner of HD :wink: dcarch __________________ tomatomatomatomatomatomatomatomatomatomatomatomato matomato tomatomatomatomatomatomatomatomatomatomatomatomato matomato tomatomatomatomatomatomatomatomatomatomatomatomato matomato