LED Christmas lights

[patscc]

I've successfully avoided 3-D movies thus far. I'm holding out for the holodeck.
Besides, I'm not sure that letting most film directors have access to another dimension is wise, considering the sh***e that comes out in 2-D.
patscc

 

[k2x4b524[]

With the 3d movies, to me, having a stigmatism in my left eye, and starting in my right eye, the 3d movie is cleared without the glasses than with them..
But i still prefer the 2d movies, always will.

I've successfully avoided 3-D movies thus far. I'm holding out for the holodeck.
Besides, I'm not sure that letting most film directors have access to another dimension is wise, considering the sh***e that comes out in 2-D.
patscc

 

[Tiberian Fiend]

I find the flicker of LED Christmas lights annoying, too. I also prefer the warm glow of incandescent bulbs. I like the large C7 and C9 bulbs, but it seems the only place to buy those now is the internet.

 

[DOS lives on!!]

This reminds me of the song, "The 12 Pains of Christmas" when the guy shouts, "Now why the heck are they blinking!" That's my only grievance with regular christmas lights. But I like coming out to non eye-aching lights on Christmas morning. It gives more of an "at home" feeling.

 

[EverythingIBM]

Because of a peculiar visual defect, I can detect LED Christmas lights flickering immediately and from a considerable distance. Lately, I've even noticed that the LED tail lamps on some vehicles have a flicker to them.

In both cases, the flicker rate is about 60Hz and to my eye is extremely irritating.

Last January, I picked up a few cheap strings of LED Christmas lights and just got them out today. Sure enough, the manufacturers use the individual LEDs in series as a half-wave configuration, so that the flicker rate is indeed 60Hz.

Regarding the LEDs, that's interesting... because I'm quite bothered by the flicker as well (particularly the blue ones: maybe because the wavelengths are closer to 380nm). I just hate it! I wasn't aware that they were flickering at 60Hz.

Good CRTs at 60Hz don't bother me... but the persistence has to be at a certain ratio. Some cheaper CRTs I used had a bad persistence, and I couldn't look at them.

I've never fancied fluorescent or LEDs, I prefer incandescent. Better hoard them before they are discontinued!

 

[luckybob]

While I don't notice flicker like some of you do, I do feel your pain. I have exceptional hearing in the high end of our hearing. In fact I can *barely* hear some dog whistles. Your fist thought might be "that's pretty cool" but its NOT. The biggest thing are the "old style" TV's. I can hear the fracking laser in them run. I always could hear anyone in the house turn their tv's on. On quiet nights, I could even hear the next door neighbors tv run. Monitors were fine, I couldn't hear those.

needless to say, I'm one of the biggest supporters of the LCD tv change.

 

[vwestlife]

While I don't notice flicker like some of you do, I do feel your pain. I have exceptional hearing in the high end of our hearing. In fact I can *barely* hear some dog whistles.

Wikipedia says "The frequency of most dog whistles is within the range of 23 to 54 kHz, so they are above the range of human hearing, although some are adjustable down into the human range."

The human range of hearing is commonly stated to be 20 Hz to 20 kHz, but some young children and a few adults can hear as high as 22 kHz, and 25 kHz is said to be the highest frequency any human has been confirmed to hear.

The biggest thing are the "old style" TV's. I can hear the fracking laser in them run. I always could hear anyone in the house turn their tv's on.

Quite a lot of recorded music has a 15.6 or 15.7 kHz tone embedded into the audio track, due to the use of TV monitors in the recording studio. I also noticed that Eric Clapton's "Wonderful Tonight" has a steady 19 kHz tone on the recording whenever his microphone is turned on!

 

[Chuck(G)]

While I don't notice flicker like some of you do, I do feel your pain. I have exceptional hearing in the high end of our hearing. In fact I can *barely* hear some dog whistles. Your fist thought might be "that's pretty cool" but its NOT. The biggest thing are the "old style" TV's. I can hear the fracking laser in them run. I always could hear anyone in the house turn their tv's on. On quiet nights, I could even hear the next door neighbors tv run. Monitors were fine, I couldn't hear those.

needless to say, I'm one of the biggest supporters of the LCD tv change.

When I was younger, I could hear the ultrasonic burglar alarm transducers used in some stores. It was painful.

Your pain will be over when you turn, oh, say, 60. High-frequency whines for me have been replaced by high-frequency tinnitus. Oh, happy day!

 

[Ole Juul]

When I was younger, I could hear the ultrasonic burglar alarm transducers used in some stores. It was painful.

Your pain will be over when you turn, oh, say, 60. High-frequency whines for me have been replaced by high-frequency tinnitus. Oh, happy day!

I remember those burglar alarms in stores. I used to yell at the staff to turn it off (while holding my ears) and they would look at me like I was crazy and I'd look at them like they were stone deaf. I assumed they were and could just read my lips since that was the only model I could come up with that would match the reality.

I'm not bothered much any more either. The ultra low frequencies still bother me as much as they did when I was a kid though. I still think the weighting scales on sound level meters is a political scam, and not appropriate to the real world.

I wonder about the LED flicker though. I used to be bothered by the flicker in most computer monitors, but haven't noticed that lately because I don't use CRTs except the slow phosphor monochrome ones. What I found interesting in this discussion is that I haven't been bothered by the Christmas lights. I have a permanent string of beautiful red ones in my living room, and a very nice shade of yellow in my bedroom - they're both on 24/7. During the recent heat wave, I had a fan in the bedroom and the flicker was very obvious on the fan blades, which seemed to go around slowly. Still, looking at the lights didn't bother me although they obviously flicker when you move them rapidly. Could my eye's persistence have increased with age?

 

[Chuck(G)]

I don't think so--I'm no youngster and I can pass by Christmas lights in my car and immediately point out all of the LED ones based on flicker--or even ones visible from a half-mile away. Things do seem darker at my age, however--I'm always turning on lights to see. My wife had cataract surgery and tells me that if and when I go under the knife, that will change.

 

[patscc]

You're seeing two frequencies "beat". The fan blade "smears" the light blip out, spatially, so your eye doesn't integrate the flicker anymore, hence you see flicker.

Speaking freaky flicker facts, the one that always gets me is when you see the flashing red & blue on a police car receding, they at some point merge into purple.
patscc

 

[Ole Juul]

You're seeing two frequencies "beat".

I certainly hope so! It's interesting how I can hear the beats better when tuning the piano than when I was younger. Some things do improve with age.

I don't think so--I'm no youngster and I can pass by Christmas lights in my car and immediately point out all of the LED ones based on flicker--or even ones visible from a half-mile away. Things do seem darker at my age, however--I'm always turning on lights to see. My wife had cataract surgery and tells me that if and when I go under the knife, that will change.

Hmm, I think there is something odd about my eyes in that regard - especially regards this flicker, which doesn't bother me now. I used to eschew TV because of the nasty look of the scanning and flicker - not to mention the headache of the HF noise. Now I'm OK with either, though I haven't seen much TV for the last 40 years.