I think deeper reds are better for nightvision than shallow or orangey reds, although 635nm is brighter than 660nm so already it has an advantage in that sense.
Personally, I like 635nm. Reminds me of the red lights of endless cars on the interstate in bumper-to-bumper traffic.
Scratch that. I like 660nm.
Hi guys
where can I source good quality 660nm deep red led emitter?...