Light Pollution

[katex]

Why is it that some sections of motoway are not lit at all - the M55 - and that is not deemed to be unsafe, while other sections - M6 - have so many lights that it is positively painfully bright.

Sorta' worked alongside this guy for 16 years who was Chairman of the Public Accounts Committe >> obviously this question was being discussed. Asked me if I thought would be better ? Could only reply, not necessary, but a damned site easier, however, did read later that lighting for miles and miles lulled drivers to sleep, more dangerous and you are more alert in unlit roads as Spuggie has pointed out.

Just think, if I had given a more positive answer, could have had the whole motorway system lit up by now.

 

[Madhatter]

There is a danger where you pass from lit to dark or dark to lit, can't remeber which way round it is.
Neil is right as usual, sodium vapour lights are the most efficient light you can get, down side being that they're orange, but that doesn't matter for roads, highlighting some buildings, and for some security purposes. Even if you used flourescents, which do get used in some signlights, they take time to warm up, so would be no good for roads.
Not that good for cameras though, but if you use a hallogen spot on a pir and shine it where its needed, down, not across, then it's not expensive to run, and not light polluting. I do agree with niel, who's right again, that a lot of the time a 150 would be plenty, especially just to light a path or small yard.
If you want constant cheap illumination for a camera, i'd use flourescents floods, although they can cause flicker on the camera, or mercury vapour , which is white like halogen.

 

[Madhatter]

On the passive sensor sensing the curtains, only thing i could think, is that you must have something hot in your room, and when you draw the curtains it blocks it. I've heard of passives picking up changes in heat through windows, but it's just hearsay, I've never encountered it .

 

[joobyjooby]

bout the only thing that does work at accy rail!!

 

[Madhatter]

I'd comment jooby but i'm not a local so can't lmao.

 

[Neil]

Asked me if I thought would be better ?

Not meaning to insult you Kate but that sounds typical of the people who make important decisions. Why on earth would he ask your opinion on something I suspect you are not qualified to comment on. Should he not have based his decision on facts relating to technical, cost and safety aspects?

 

[Neil]

or mercury vapour , which is white like halogen.

Metal Halide provide a nice white light and are efficent. They are a discharge type light so take a few minutes to warm up. They can usually be used on SON gear so can be used as a direct replacement. Many of the new street light fitted around us are now white and I suspect they are using metal halide lamps. Only problem for home use is they are quite expensive compared to a £5 150w B&Q halogen light fitting with PIR.

 

[chav1]

I'd comment jooby but i'm not a local so can't lmao.

dont they have lights where you are ..?

if you want we can start a thread about annoying candles

 

[katex]

Not meaning to insult you Kate but that sounds typical of the people who make important decisions. Why on earth would he ask your opinion on something I suspect you are not qualified to comment on. Should he not have based his decision on facts relating to technical, cost and safety aspects?

Sure it was decided on all aspects here Neil and definitely not on my humble opinion, and was just 'off the record' as someone who did an enormous amount of driving, how I found the difference between lit and unlit motorways. Nowt wrong with that, is there ? As you know, the Public Accounts Commitee are the watchdog on all Public spending and cost/ safety and all technical aspects would have been the main criteria as well as users experiences.

 

[Madhatter]

dont they have lights where you are ..?

if you want we can start a thread about annoying candles

We have gas lights. We have a railway station, thats not got a ticket office chav, i only commented that i agree yours shouldnt be closed, and that appearance is everything and got bad karma and told to find a local forum.
This is a local forum for local people chav.

 

[Madhatter]

Metal Halide provide a nice white light and are efficent. They are a discharge type light so take a few minutes to warm up. They can usually be used on SON gear so can be used as a direct replacement. Many of the new street light fitted around us are now white and I suspect they are using metal halide lamps. Only problem for home use is they are quite expensive compared to a £5 150w B&Q halogen light fitting with PIR.

You are of course correct, and I was thinking that going up the motorway to the meet. they don't put sodium lights on the motorway do they, they're mercury vapour, the golden ones, and the crisp white which are appearing more often now, as i assume costs are falling, are metal halide.

 

[Neil]

Mercury vapour are also white. I think they are very similar to the newer metal halide ones. I think the old orange street lights were a very efficent type of low pressure sodium but not nice to look at. The modern high pressure sodium (HPS) lamps are more yellow and are often used as motorway lights. You can also use high pressure sodium lamps for growing plants as in this example I found on the net

 

[Madhatter]

lol you naughty naughty boy stealing pictures of marajuwana

 

[Neil]

OMG is that what it is?