# Green Shooting Lights for Hog Hunting - Laser vs LED



## funkychateau (Jan 13, 2012)

I posted this question on the DX forum, but thought I'd try it here as well.

There seems to be some consensus (maybe?) in the hunting community that colored lights are less startling to wildlife than white lights. 

I'm designing a weapon light for use with a scoped rifle at night. Currently I'm considering a green Cree LED combined with an aspheric lens to shoot from a blind approximately 75 yards away from my feeder, which is also equipped with green lighting (though not bright enough for shooting).

The light divergence needs to be pretty tight, covering the scope field of view without appreciable side spill. 

I will be mounting the light on the weapon (not hand-held). The mass of the aspheric lens setup is not inconsequential, and it occurred to me that I might also be able to use a slightly-defocused laser as an illumination source, which could result in a lighter device.

Assuming it is readily possible to "spread" the laser beam to around 5 degrees or so divergence, how can I calculate a relative-brightness comparison? LED outputs are specified in lumens, lasers in milliwatts. If I have 100 lumens of green LED light covering a 10-foot-diameter spot, how much green-laser power is required to achieve the same effective "brightness" when defocused to the same spot size? In other words, can we come up with an approximate total-flux conversion from output lumens (LED) to output watts (laser)?


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