led Christmas tree strings - Any experience here?

[begreen]

Seems like the laser christmas lights is better for large areas or big trees. But looks like I should pass. We are just 5 miles from SeaTac airport. Shining it at a tree means that there will be many beams not hitting the tree and heading into the sky. Too bad, we have some nice big trees including an 80 ft redwood in the front yard.

 

[semipro]

I can't help but wonder if the FAA isn't going to have a problem with these things impairing pilot vision.

Edit: Funny, I wrote this as begreen was writing about being near an airport.

 

[woodgeek]

IMO, there is zero issue with conventional laser pointers and aircraft. The issue was high power green laser 'pointers' that went on sale a few years back that were so powerful (up to 100x brighter than a normal pointer) that they could light items on fire, and were too bright to be used as actual indoor pointers (they were painful).

In the 'star shower' case, each sub-bean is significantly less bright than a normal laser pointer (i.e. quite invisible in the daytime). Moreover, I noticed that each of them has a slightly converging quality with a weak focus at several meters....at aircraft altitude, these beams would be several meters across.

 

[Sprinter]

Last night we went to a Christmas program and they were using something similar indoors to project star-like pattern to the front where the program action was. It was a nice effect and the stars were about the right distance apart. They were blue, but it looked like they covered up part of it either for colors or to spread the pattern.

Apparently, these most popular projectors do have a warning not to use them within 11.5 miles of an airport. There apparently have been three reported incidents from pilots from these devices. If you can be sure that the beams are not pointed upward, they shouldn't be a problem. Maybe just mount it high enough to point horizontally or something. Still, the FAA is nervous about them. Way too many irresponsible people out there.

This is a very good article on laser safety I came across that addresses these devices: http://www.laserpointersafety.com/news/news/other-news_files/tag-star-shower.php#on

 

[woodgeek]

Nice link. Reading down, lab tests suggest that the (brighter) green laser 'beamlets' could cause 'glare' issues at up to 269 ft, and were eye safe at all distances. This jibes with my own expectations.

 

[Sprinter]

Nice link. Reading down, lab tests suggest that the (brighter) green laser 'beamlets' could cause 'glare' issues at up to 269 ft, and were eye safe at all distances. This jibes with my own expectations.

Frankly, I don't know what to think about the potential hazards of theses things. I use a common green pointer sometimes to point out certain astronomical objects to people because the green beam at that wavelength is so nicely visible straight out. It's like it's really pointing right at something light years away. But I'm aware of any aircraft (easy at night), and having flown quite a bit as a private pilot (many years ago) I'm sensitive to it, and the power of these are quite low.

Personally, I'm more concerned about the irresponsible people using the high power lasers, often intentionally. Green is the eye's most sensitive color which may contribute to the glare problem mentioned. Obviously, any such devices should not be used any where near an airport. Flying on autopilot and half asleep (not that I ever was!) is one thing, but if you are on an ILS approach or something, any distraction like that could have very unfortunate consequences.

Having said all that, I think that assuming you are a responsible person, not near an airport, and use one of these things in such a way that the beams are pointing down, horizontal, or fully on an object like a house, you should be okay IMO.

Still, be aware that the FAA is concerned, and nervous pilots may report things that could cause a knock on your door.