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Old 07-05-2012, 06:41 AM   #7
theblondskeleton
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Default Optics

7. Optics/Reflectors

What is the difference between optics and reflectors?
Optics include a lens that bends and focuses the light into a smaller, more concentrated cone. Reflectors include a shiny surface that bounces the light in another direction.
Do I need them? If so, which ones do I need?
Optics limit the beam spread of an emitter. Most emitters have a beam spread of about 120 degrees. Optics come in many beam spread options including 40, 60, 80, 90 degrees, and others. The particular beam spread you use will depend on your preference in fixture height, spacing, tank size, and how you plan to keep the light out of the viewerís eyes.

High-power LEDís are dangerously bright. Most of us view our lights from below the level the fixture is hung from. If you donít consider how you will limit spillover, you could harm yourself or others with these very bright emitters. If you are building an enclosure for your fixture, this may not be an issue.
Will reflectors increase my PAR?
Hoppy has mentioned that reflectors do not appreciably increase PAR from the emitters.
What optics do you recommend?
A lot of all-in-one packages use 60-degree optics. My own fixture uses these as well.

Last edited by theblondskeleton; 07-08-2012 at 02:47 AM.. Reason: Update info
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