ChatNoir
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1 foot = 30cm
1 cm = 10mm
I have been researching light for some time, and came up with some data. I wanted to share it.
As far as we know, light diminishes directly proportional to the square of distance (d²).
I will be using a lot of calculations in here so get ready, also I must admit that my information is based on calculation and theoretical information.
While researching lights, I came up with a fluorescent tube you will see in attachment. It has just the right spectrum as well as 90~lm/w efficiency. I am assuming all tubes are within proximity of 6cm of plants for our setup. It is a fluorescent tube, 1213.6mm in with 28mm in diameter. 3250lm light power and 6500K in light colour.
We will be using our control as widely used 400W MH lamp with 53,000 lumen output, 123~lm/w effectivity as well as 280mm in lenght. I am assuming, it is housed in a tempered glass cage and hang within 30cm proximity of plant.
Our plants are assumed to be 60cm (2 feet long) and 40cm (4/3 feet) wide. In a 130cm (4 and 1/3 feet) long, 60cm (2 feet) wide cabinet.
We will be using one 400W MH lamp above the plants and in the middle, and 10x3250lm fluorescent lamps around the plants 4 on the top, 3 on the side with 10cm between top lamps and 17cm between each other for the side lamps. We will calculate four different values for both lamps; the lumen value at the bottom of the middle plant, the lumen value on the top of the middle plant, the lumen value on the top of the rear plant, the lumen value on the bottom of the rear plant. Those are point calculations, they do not include rebounding light and for MH lamp, we are ignoring the canopy opacity.
Relative Lumen Values for MH Lamp
Top: 58,0~
Bottom: 6,5~
Rear Top: 21,2~
Rear Bottom: 6,0~
Relative Lumen Values for Fluorescent Lamp
Top: 152,8~
Bottom: 141,7~
Rear Top: 152,8~
Rear Bottom: 141,7~
My conclusion is fluorescent lamps are much more effective in vegetative growth. Please correct me if I am wrong.
1 cm = 10mm
I have been researching light for some time, and came up with some data. I wanted to share it.
As far as we know, light diminishes directly proportional to the square of distance (d²).
I will be using a lot of calculations in here so get ready, also I must admit that my information is based on calculation and theoretical information.
While researching lights, I came up with a fluorescent tube you will see in attachment. It has just the right spectrum as well as 90~lm/w efficiency. I am assuming all tubes are within proximity of 6cm of plants for our setup. It is a fluorescent tube, 1213.6mm in with 28mm in diameter. 3250lm light power and 6500K in light colour.
We will be using our control as widely used 400W MH lamp with 53,000 lumen output, 123~lm/w effectivity as well as 280mm in lenght. I am assuming, it is housed in a tempered glass cage and hang within 30cm proximity of plant.
Our plants are assumed to be 60cm (2 feet long) and 40cm (4/3 feet) wide. In a 130cm (4 and 1/3 feet) long, 60cm (2 feet) wide cabinet.
We will be using one 400W MH lamp above the plants and in the middle, and 10x3250lm fluorescent lamps around the plants 4 on the top, 3 on the side with 10cm between top lamps and 17cm between each other for the side lamps. We will calculate four different values for both lamps; the lumen value at the bottom of the middle plant, the lumen value on the top of the middle plant, the lumen value on the top of the rear plant, the lumen value on the bottom of the rear plant. Those are point calculations, they do not include rebounding light and for MH lamp, we are ignoring the canopy opacity.
Relative Lumen Values for MH Lamp
Top: 58,0~
Bottom: 6,5~
Rear Top: 21,2~
Rear Bottom: 6,0~
Relative Lumen Values for Fluorescent Lamp
Top: 152,8~
Bottom: 141,7~
Rear Top: 152,8~
Rear Bottom: 141,7~
My conclusion is fluorescent lamps are much more effective in vegetative growth. Please correct me if I am wrong.