White street lamps update

[Doggle Avaddit]

The white lighting technology used here in Leeds is Metal Halide.

Here is one manufacturers website:

Metal Halide


Interestingly it claims that the colour emitted can be easily designed into the lamps, i.e. you can generate almost any colour you like. ("Specialty colors, including blue, green, aqua and pink, can also be produced")
It also mentions the fact that the lamps have inbuilt dimming capability down to 30%.

[nytecam]

Thanks for the link - their website doesn't state that the halide lamps emit at descrete wavelengths [as my spectra of white street lamps hereabouts indicate] so I've emailed US HQ for tech details including spectrum. The fact they can make the lamps any colour to order is worrying [for some!]

Suppose unless you're deeply into astro under skyglow light pollution it's of little concern to most folk who'll appreciate a nice 'natural' non-yellow street light nearby but bet if they caused critters to go belly-up there'd be outcry hereabouts

[Doggle Avaddit]

The company who won the Leeds contract are said to use Philips Cosmopolis light systems:

Philips CosmoPolis


If you get no joy from my first link, then maybe try emailing them too.

[Jez]

I wonder if these will have the blackbirds singing all through the night?

[Doggle Avaddit]

Nytecam, I don't know how relevent this may or may not be, but this has a large selection of Metal Halide lamps, and if you click on each one you will also find its spectrum.


Quite a variation there!


MBI Quartz

[dampflippers]

All out street lamps have been changed to low energy white ones. I think we can now see more stars than before, so isn't that good? Or is there another problem?

[nytecam]

Originally Posted by Doggle Avaddit

Nytecam, I don't know how relevent this may or may not be, but this has a large selection of Metal Halide lamps, and if you click on each one you will also find its spectrum.
Quite a variation there!
MBI Quartz

Thanks for that - I've overlaid the three most prominent nebulae emission lines onto one of the lamps and it would appear [for that lamp only] that current deepsky nebula filters for Ha and OIII will suppress the remainder of the lamp's spectrum that's added [inevitably] to skyglow however well shielded - so it's good news [for some] May get around to the other lamps spectra sometime

ps:this particular MH lamps seems to have the similar spectrum to one I look locally posted above so there's hope!

[nytecam]

This second MH lamp with rare earth elements? is troublesome for the major H-alpha emission from nebulae and probably can't be filtered out at the telescope One wonders why lamp manufacturers can't be a little more savvy when designing a street lamps - this sample would be a clear brick job for nearby deepsky astronomers

Checked some other MH lamps listed and the 'daylight' versions emit virtually thoughout the whole spectrum [as a continuum] - like daylight... ho-hum and can't be filtered out - drat.