led optics

billyzbear

Active member
I read on here someone had a program that would tell you coverage of different optics at different heights. I've been looking everywhere for one and finding nothing.
I need to know if a 90 degree optic will cover x amount of area at x amount of height. Height of most interest would be 5".
 
Use grade school geometry. I had to when i was trying to figure out what the diameter of each led's light would be at about 2 feet from the sand bed. Just use a right angle, as the one angle, 3 feet as the height, and half of the angle of the optics for the top angle. So for a 90 optic. Use 45 degrees at the top angle, 90 as the bottom right angle, and whatever height you want for the distance between the 90 and the 45 degree. Then when you get the measurement for the length opposite of the optic you double it to get the full distance.
 
Thank you sir.
If I had a protractor it would be easy...

At 90 degrees Tan 45 which is 1 ....sooo for every 1" off the water the spread is 1" on each side ie. 2" diameter circle.. Roughly.. The complications come in w/ the real optical path and of course the LED is not equal strength at every degree (higher intensity more in the center than at the edges)

90 degree optics and 6" off the water line will light a 12" diameter circle..

tan30 degrees (60 degree lens) = .577 At 6" up you have coverage at 3.46" radius x 2 = 6.92" circle.....

90 degrees at 5" covers a 10 inch circle.. ;)
 
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Optics

Optics

I put some RB leds on my 180 with 90 degree optics if you looked from the side you could see the cone of light in the water.
 
Looking to get more out of my leds.
I'm seriously thinking of adding some more t5's. It seems that my sps and everything grew better with them. I do love the RB though...
 
T5 led

T5 led

I have my t5 and led just the royal blue I like the color with the leds and use the t5 for day light.
 
If you have a led with a 90 degree optic and another led same color with a 60 degree like 2" away. Would the 60 degree beam stick out?
 
If you have a led with a 90 degree optic and another led same color with a 60 degree like 2" away. Would the 60 degree beam stick out?


for a distance .. yes.. overall not likely visually, though a photograph will pick it up....... AT 1 1/2 inches away from the diode (roughly) the cones will converge..

It gets complicated..
This is an example w/ 120 degree lenses..but you can picture different cone angles.
LEDarrayguess.png


rough approx.. square = 1"
rough.jpg
 
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