TheGreenButton - Windows Media Center Forums

STC wrote:

barnabas1969 wrote:You need a dimmer that is designed for LED's

You also need LEDs that are designed to dim. That's why the dimmable ones usually come with the dimming electronics ready to go.

Ah! Too many nuances. Now I'm started to think *I'm* dim!

These are much better than the ones from Ikea.
They are dimmable and do remember last setting including brightness if power is lost.

http://www.ebay.com/itm/5M-12V-IP65-Wat ... 3cce462e58

You can spend a little more to get a remote with more functions but it isn't really needed for a lighting TV application.

I wasn't going to buy at ikea... just saw it there first as an example. This is what I was thinking:
http://www.amazon.com/HitLights-Flexibl ... WOIMZ6R5N3
http://www.amazon.com/Ledwholesalers-In ... Z8QL4ESJPV

Looks good. You'd still need the 12v PSU.

STC, I have that exact setup (the one you listed on e-bay). Yes, it does forget the last setting when power is lost for longer than 30 seconds or so.

Also, all of the DC-powered LED light strips are dimmable. If the strip has it's own power supply so that you can plug it directly into an AC power source, then it needs to be specifically designed to be dimmable. In the case of the AC-powered LED's, you would use a normal triac-type dimmer (if it's rated to work with CFL's, it will also work with the AC-powered dimmable LED's).

Hmm we have one on a display that appears to keep the last setting when powered off for a while i.e. electrical storm all power lost for a period of hours. I shall investigate.

As for the dimming I specifically mean LEDs designed for dimming ramp up and down much more smoothly across the full range than ones that are not.

Both of my controllers return to bright white after a power failure that lasts long enough to drain the capacitor in the power supply. The saved custom color presets remain, but the last state is lost.

DC-powered LED devices are all dimmable. How smooth it ramps up and down is exclusively a function of the controller. Individual LED's themselves are not dimmable (they are fully-on at the rated forward voltage, and fully-off below the rated forward voltage). The dimming is actually a function of the PWM controller. When dimmed, the LED's are actually flashing faster than your eyes can see (typically about 10KHz). The duty-cycle (the percent of "on" time vs. "off" time) is what creates the illusion that they are dimmed. If the controller can smoothly ramp the duty cycle, then it will appear that the LED's are smoothly changing in brightness (and/or color for the RGB LED's). Both of my controllers have some settings to smoothly change from one color to another (automatic color changing with variable speed). However, the manual brightness control is anything but smooth. It only has a fixed number of increments for the manual adjustment.

AC-powered dimmable LED devices, like the Sylvania line of dimmable, screw-in incandescent replacement bulbs, have a special controller built-in that detects the duty-cycle on the AC line. The AC duty-cycle is controlled by a normal dimmer switch just like what you would use for an incandescent bulb (using a phase-cut circuit). The power supply (internal to the bulb) then adjusts the DC duty cycle to the LED's accordingly.

Okay well I checked our display LEDs and barnabas is correct, they do not retain their settings after a longish cut of power. It appears my wife 'reset' them to our desired setting last time we had a power cut and power was restored. I assumed they retained their last setting.

I have a two year old white 4 pin 12v strip that I attached to a controller I got with a newer white strip. Both are 10 feet.
Both strips exhibit very different actions when controlled by the same controller on the same settings. That's what I was trying to get at.
They both do 'dim' but perform to varying degrees. I believe this to be due to design and specification differences.
The older strip did not come with a dimmer.

I can definitely see the possibility that different strips could have different specs for the LED's. Color temperature of each of the three colors can vary and so can light output. I even found one strip to be wired differently so that the colors were different from the next strip in series. I had to re-wire it so that the same conductors were used for red, green, and blue as the other strip.

Yes indeed. For instance, the two lowest dim settings don't fire the older strip at all.

For a more integrated solution I came across this. Basically hdmi in and out to tv and the processing and driving is all done in the box. Available soon too by the looks of things....

http://www.keiang.de/Content-pid-32.html

apbms1 wrote:For a more integrated solution I came across this. Basically hdmi in and out to tv and the processing and driving is all done in the box. Available soon too by the looks of things....

http://www.keiang.de/Content-pid-32.html

Wow. That's pretty cool. I don't think I want to do that for my TV, but I didn't know the 28xx addressable LED strips existed. Those would be perfect for outdoor Christmas displays. I've wanted to be able to (affordably) control the color of individual Christmas lights since I was a kid! Turns out that there's actually a forum for that! Way cool.

That's the kind of mulit-colored lighting that I was talking about earlier. I agree that it looks cool, but it fails to serve any purpose beyond that (aside from being distractive).

richard1980 wrote:That's the kind of mulit-colored lighting that I was talking about earlier. I agree that it looks cool, but it fails to serve any purpose beyond that (aside from being distractive).

It's an immersion/additive feature for certain content - not all, but some. Just cause it's not for you man doesn't mean it serves no purpose. Just means it's not for you/you're not the target audience. Some people find background noise like a TV on or music playing when they're working distracting - some can't get work done without it. Different strokes for different folks.

staknhalo wrote:

richard1980 wrote:That's the kind of mulit-colored lighting that I was talking about earlier. I agree that it looks cool, but it fails to serve any purpose beyond that (aside from being distractive).

It's an immersion/additive feature for certain content - not all, but some. Just cause it's not for you man doesn't mean it serves no purpose. Just means it's not for you/you're not the target audience. Some people find background noise like a TV on or music playing when they're working distracting - some can't get work done without it. Different strokes for different folks.

It would be cool for video games. Not sure I would want it while watching TV though.

Another use is for when you have a fullscreen visualization playing w/ music.

staknhalo wrote:Just cause it's not for you man doesn't mean it serves no purpose.

I didn't say it serves no purpose...I said it serves no purpose beyond looking cool. In other words, the benefits of bias lighting are not realized with this kind of lighting.

I bought this:
http://www.amazon.com/gp/product/B007TG5EG8/

Plugs into the USB port on the TV. So it lights up when the TV is powered on, and turns off when the TV is powered off. There is also an on/off power switch on the cord, so you can leave the light off even when the TV is powered on.

Nice

rayw69 wrote:I bought this:
http://www.amazon.com/gp/product/B007TG5EG8/

Plugs into the USB port on the TV. So it lights up when the TV is powered on, and turns off when the TV is powered off. There is also an on/off power switch on the cord, so you can leave the light off even when the TV is powered on.

Oooh, this is exactly what I'm looking for, and much cheaper than any other kit or a la carte options I was looking at.