h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

"Meat" means people, too - anyone being illuminated will look less attractive - sallow and ill - so especially don't use them for romantic trysts!

Anything normally red will look greyish. Some of the green spectrum goes missing, too.

>> they use dangerous materials in their production, including quicksilver, which can leach into the ground if they're simply dumped. They're hazardous waste! <<

I think that this particular factoid has been disproved as there's more mercury in a tin of tuna (OK, that's quite a lot! ) or a Queen album (quite a lot of Freddie Mercury, but hardly any element with atomic symbol Hg) than in an energy-saving lightbulb.

RF

Assuming 0.353 ppm mercury contamination in a tin of tuna (according to the Chicago Tribune ) and 300g of tuna per tin, that makes 0.11 ppm - or 0.11 mg - per tin.

A CFL has 5mg of mercury - and it's "free" mercury, which makes it more dangerous, as it can vapourise and be inhaled.

Er, no, sorry. That makes it 0.11 mg, *not* 0.11ppm, that stays the same!

we have low energy bulbs all over the house, our red bedroom walls still look red and as for the dinning room the food looks wonderfull and i can still see the blood when i cut myself shaving in the bathroom.

Malabarista, you probably got a duff batch!!!!!

No, you probably have advanced full-spectrum bulbs - they still won't have the full spectrum, though.

I've had to sit through hours and hours of lectures about this, and do experiments comparing light spectrums Even the "daylight" ones are missing a lot.

Being a wife who has had to suffer from multiple (+++) conversations about energy saving bulbs and the variant colour intensities of them, I will refer this conversation to t'other half in the morning and he will no doubt regale you all with the specifics!

Hope you are all as interested as I am! I just want a loo light that lets me pee in something approximating daylight!

"Is it more environmentally-friendly to use up all the old-fashioned lightbulbs that I have, or replace them immediately with low energy ones?"

It's better to use up what you have first and replace when they go, or as I've done, keep them for spares (although I've kept mine for spares for a very long time now).


"The colour temperature isn't the same. The reason they seem to not be as bright is that while the output lumens are the same, they're missing nearly the entire red spectrum."

As I've said before, the cheaper the bulbs, the lower quality you get and of course the free bulbs are always the cheaper ones. I've used these bulbs for years and either am now used to it or have good enough quality bulbs to be as close to old-style bulbs as possible.

this is correct. your brain will fill in missing colour spectra. which is why things stop being blue, yellow or red moments after you put on a pair of sunglasses. moving from a room with incandescent light to a room with fluros, the colour issues with both types of lighting will be immediately evident however.

Perhaps that is where I am going right then - I've only got one or two old-style bulbs left in the house now, so I see by this light all of the time.

My little LED reading light (the ones that grip the book) looks very blue to me sometimes.

That's because the cheaper LEDs also emit blueish light - though truly blue LEDs are the most expensive as they have the smallest spectrum.

Your brain may be used to it enough to distinguish colours - but don't try matching fabric colours, putting on makeup, etc. by that light!

I couldn't match a colour if I was in broad daylight anyway.

I sort my threads out with this light, and never have any problems. Unless I'm dealing with 20 shades of brown, when again, I'd have trouble even in broad daylight...

Depends what you like I guess. Normal bulbs are fairly indiscriminate and cover the entire visible spectrum like the sun, so look more 'natural' to most people. I quite like the coolness of fluorescents though.

Most white LEDs are, IIRC, blue LEDs with a white phosphor coating, similar to fluorescents (white being a product of many different frequencies). I bought a couple of GU10 LED bulbs the other day, and was somewhat disappointed that their output wasn't stated on the packet, and they turned out to be a bit rubbish. Certainly not sufficient to light a room.

We replaced all our halogen downlighters in the kitchen with led ones...then promptly switched at least half of them back again as they are rubbish (and very expensive!) - either too blue, too yellow, or just too dim. We've got a couple with mini fluorescent bulbs in that start off rubbish and work up to almost acceptable.

But not found a good enough alternative to the halogens yet so will stick with having a mixture of all three sorts until the technology catches up.

ordinary incandescent lights have a distinct bias to yellow. most photographers would be aware of it because it needs to be factored in when taking pics under this sort of lighting.

DNA has a rather poetic passage about light spilling from a home onto the street in one of his books. one of the dirk gently novels perhaps? i can't recall.

leds are currently only suitable for spot lighting. i expect that will change soon.

I got the free bulbs from the gas company, they are the 60w and 40w equivalent ones.

I have wondered why the most they do is 100w equivalent. If they made 200w equivalent it would still be less than the original 100w and save energy and may actually BE equivalent to 100w.

As I also don't have a car, I am going with the keep the broken ones in a cardboard box for now idea.

I am guessing that the whole business of what the UK is to do with waste electrical stuff will become a bigger problem needing a solution before my house gets full of boxes of used light bulbs because all the companies seem to be using the "pay to fund the council tip" option.

Irony is that my free energysaving bulb from the gas company went in about a month of being putting in!

Take it back then. They do have a guarantee.

: Like RF (I think), above, I've never recieved a single free lightbulb
Though, thinking about it, isn't it really quite irrisponsible, environmentally, for groups/companys to randomly send out free lightbulbs?: Sure I imagine most people will use em, most people have lights in their hosue I guess, but I guess a certain percentage do get tossed straight in teh bin (as I do with the free tea samples I keep getting; tried them once and as they were disgusting I know throw them out, fairtrade they might be but drinkable they ain't)... I can't remember the last time we changed a lightbulb, mind, I've just had the lights in the kitchen/studeo/ultility rooms fixed, which haven't worked for nearly a year, which i gues sis another way to save on the energy spent on lighting.... Actually I don't think the spare room or my bedroom has had a light bulb that works in at least half a decade I think I'd stand a better chance of saving energy by putting up a washing line and not using the tumble dryer if only were there space to put a line
I've a friend who's quite into all the 'green' stuff, and he seems to get on well with the new LED lights, though he still uses a traditional bulb in the reading lamps which seems to kinda make sense I guess... spose I might look into energy saving versions if I ever put bulbs in teh bedrooms again, at least they might last longer which would make up for my inability to be bothered to put bulbs back in once they're blown

Traveller in Time with a new stairway light
"I am busy mounting motion detection switches combined with light sensors, the stairway will be illuminated for one minute after the last motion during darkness. The illumination is by strings of white LEDs and all is powered by a switch mode power supply.

Power consumption in standby is less them 1 mA full illumination less then 150mA at the 5V circuit. "