Indoor LED Lighting

[Ian Stirling]

Well - maybe. A lantern is one situation in which LEDs actually work well. The problem is that the cheap driver circuits found in 'camping' lanterns are inefficient.

Also, small fluorescents have quite poor efficiency.

In comparison, the driver circuitry for LEDs can easily be 70-80% efficient, without really trying, and 90% isn't remotely difficult.

Hmm. Annoyingly I can't find figures on the web. I'll look tomorrow to see if I can find the packaging for the lantern I have. Otherwise I'll try some actual measuremet.

Not all LEDs are directional, and ones that are can be diffused.

There is also the fact that LEDs dim efficiently - CFLs don't really.

[Dave Plowman (News)]

A lantern to me emits near omni-directional light. You'd need quite a few LEDs to do this.

I can only talk for the very small LED and fluorescent lights used for filming in cars etc, and the fluorescents still have the edge in battery life.

The interesting thing is there are no legal replacements for a standard car stop light bulb etc in LED - despite multiple LEDs firing in all directions it's not possible to get the even 360 degree emission of a filament bulb in a fitting designed for that.

CLFs may not but fluorescents can and do.

[The Nomad]

Yes,

Wonderful!

Nick

[Ian Stirling]

I'll point everyone at

for more info.

[Ian Stirling]

There are LEDs which emit pretty evenly into a whole hemisphere. Add a small reflector to spill the light into a horizontal beam, and they are just about there.

It's only really been in the last year or so that LEDs have caught up.

Not really - the voltage drop at the electrodes increases as the current goes down, and the heater power remains a constant, this makes the efficiency drop through the floor as they get very dim - say 10% light output.

[Ian Stirling]

from the same dealer, reopened.

1AA, 4 quid or so.

[The Natural Philosopher]

I have to say I read that as "makes the efficiency drop (through the floor). As they get very dim - say 10% light output".

I was going to remark that illuminating things through floors IS pretty inefficienct.;-)

[Ian Stirling]

This is what glass ceilings are good for. (on the floor below).

[The Natural Philosopher]

And there was me thinking it was all a feminist conspiracy.

[dmc]

In article ,

Errrr....

Am I missing something? Can they really be selling little led keychain torches in packs of 10 (including batteries and delivery from Hong Kong) for $4.70??

a pack of 4 laser pointers with led torches for $4.99?

Where is the catch here (and they take paypal it seems...)

Is this somesort of dodgy phishing attempt? I must admit to being kinda tempted ;-)

Darren

[Ian Stirling]

Yes.

Of the pack of 10 I bought, one was a bit broken, and needed dissasembly, and reassembly.

Though I bought assorted other stuff at the same time, so diddn't get the free shipping.

Again, yes.

As I understand it, how these people work is to buy several containers of stuff, then sell it.

They run into considerable problems with the suppliers, as they sell the stuff cheaper than the normal retail channel, so tend to change names often.

They are one of the commonly used suppliers for cheap stuff on

- though they have no relationship with it, and there are few complaints, and reports of refunds for broken stuff.

Of course, I can't say that they will actually continue to deliver.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Ian Stirling saying something like:

I bought one of these recently...

wee thing, it is.

[Ian Stirling]

Personally, I hate the annoying multiple battery, changing 3AAA cells is a lot more fiddly than just changing an AA cell.

Not to mention that it's annoying to find a dodgy cell if there is one.

I'm buying another 10 of the above. Some of them may get upgraded with a brighter LED (same power) for around 3-4 times more light.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember "Bob Eager" saying something like:

are selling an LED torch bulb conversion for a fraction of the price. I've ordered one to see if it's any good, and if so will buy some more.

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Grimly Curmudgeon saying something like:

Turns out it's pretty disappointing. OK if your eyes adapt to it and it's pitch black outside, but overall crap. Another minor glitch is the focal point on the torch - in an adjustable focus torch it's bearable, but on most lantern types it's awful, just serving to further dilute the pitiful light output.