LED vs SOX cut-off/spill angles

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Cian
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LED vs SOX cut-off/spill angles

Post by Cian » Thu Jan 10, 2019 16:54

I'm not sure I've got the right terminology for the title there...

My local council has begun LED rollout fully now and as part of it, is performing all casual replacements with new LED lanterns atop the existing poles. The majority of lighting being replaced is SOX as they did a full rollout of this (including lantern replacement on existing poles in many cases - some are now on their third bracket and lantern!) in the 1990s; but there was a period of CFL lamps in existing lanterns.


I'm fairly convinced that the light does not spill as far from the lights as before - but this may be because it isn't as obvious due to being white vs orange. My own street has ridiculously spaced lights so if this is actually the case, the unlit gaps are going to get wider

Is this likely to be the case? Can't ID the lanterns because I've no experience in doing so, should there be a significant variance there.

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Skye
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Re: LED vs SOX cut-off/spill angles

Post by Skye » Thu Jan 10, 2019 17:28

Councils should redesign their lighting schemes to compensate for LED lanterns with cut-off light distribution patterns. This usually means installing new columns at a narrower spacing between them. Most of them don't as it is not a priority for the funds they get.
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Cian
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Re: LED vs SOX cut-off/spill angles

Post by Cian » Tue Jan 15, 2019 23:32

I wanted to make sure I wasn't imagining stuff before I started moaning about it.

Local councillor, who is an electrician and I'd hope might know enough to refuse to pass on something stupid about lighthing, has put a motion down in relation to ensuring that replacements are equivalent in coverage due to me asking. They were involved in the SOX rollout push in the 90s so they did know what they were talking about then anyway!

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Re: LED vs SOX cut-off/spill angles

Post by ravenbluemoon » Thu Jan 17, 2019 23:06

Given they've just replaced the lantern on the side road next to my house, I can say that there's a lot more cut off compared to the original (~10 year old due to previous damage) SOX lantern. As it is right outside my kitchen and upstairs landing window, I was almost used to walking through without switching the room lights on. Now it is really too dark to do that. My neighbour is actually considering a security light for her front door as she can't see out very well at night, and so won't open the door after dark.

There's not a perceptible difference in brightness between the old and new when on the street. However in the area where it was simply a "head swap" and not a full replacement, it is noticeable that you get a very distinct dark spot between lampposts.
"Down at the Ferrybridge junction
Beneath the cooling towers a man stood hitching a ride
And in the long grass at the side of the road his son was laid asleep
He said - nothing's left to keep us in the city where we come from
Take us far away from here - looking for work and the wishing-well"

Tales of the Road - Justin Sullivan, 2003

Dorman-Smith
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Re: LED vs SOX cut-off/spill angles

Post by Dorman-Smith » Wed Feb 20, 2019 14:50

On our estate they replaced all the SOX lamps with LED, didn't replace/add poles and it now resembles the Victorian gas lamp era from the point of poor illumination, but they claim it to be acceptable and safe, strange how they have left the SOX lamps in place by the Zebra crossings, so I think from that we can read that SOX is a safer illumination maybe?

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nowster
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Re: LED vs SOX cut-off/spill angles

Post by nowster » Wed Feb 20, 2019 21:41

I was musing on this the other night when another ninja pedestrian was crossing the road.

I have a theory that the angles of new lighting are all wrong, causing top-down illumination only, or deep wrong-side shadows when near to a street light and the shadow side is facing traffic.

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Stevie D
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Re: LED vs SOX cut-off/spill angles

Post by Stevie D » Wed Feb 20, 2019 21:56

Cian wrote:
Thu Jan 10, 2019 16:54
I'm not sure I've got the right terminology for the title there...

My local council has begun LED rollout fully now and as part of it, is performing all casual replacements with new LED lanterns atop the existing poles. The majority of lighting being replaced is SOX as they did a full rollout of this (including lantern replacement on existing poles in many cases - some are now on their third bracket and lantern!) in the 1990s; but there was a period of CFL lamps in existing lanterns.


I'm fairly convinced that the light does not spill as far from the lights as before - but this may be because it isn't as obvious due to being white vs orange. My own street has ridiculously spaced lights so if this is actually the case, the unlit gaps are going to get wider

Is this likely to be the case? Can't ID the lanterns because I've no experience in doing so, should there be a significant variance there.
We have had LED lights inflicted on us round here, and they're horrible. They cast a much more defined light pattern, which means that the road is well lit (there don't seem to be too many gaps but I can imagine if the existing posts were just a little further apart then there would be dark spaces between them) but anything off the road is in deep gloomth. There's pretty much no light bleed up to my front door now, so I'm fumbling keys in the dark and barely able to see the keyhole, whereas before there was enough light spread that I could see clearly, although not so much that it was disturbing from inside the house. The light is also noticeably harsher than the soft amber glow that we were used to, and the shadows deeper – it may be cheaper for the council to operate, but it is a far less satisfactory result.

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Re: LED vs SOX cut-off/spill angles

Post by traffic-light-man » Thu Feb 21, 2019 08:42

Given my background in theatre lighting, it was quite noticeable when LED stage floods hit the market, particularly at the cheaper end. What was previously something similar to what you'd have lighting up your back garden, using a traditional tungsten lamp and outputting around a 130 degree light dispersion was now a panel of LEDs, but with a very tight spot of light in comparison, sometimes even down to 20 degrees or so. Things are a bit different these days because the manufacturers look at LED fixtures much more seriously, particularly now that LEDs have progressed so far and different lenses and optics have been developed for finessing LEDs specifically.

Back to street lighting - having said that, in my experience locally, it seems most LED fixtures for road use are still just a panel of LEDs, and a lot of them have a tight spot rather than the traditional flood of light. There's obviously something to be said for the fact that traditional lanterns with a lamp use engineering of reflectors and lanterns to give the desired output, whereas with LEDs it is usually much more about focussing an individual LED using optics and the right LED in the first place.

St Helens used a lantern that had a curve to the face of it that would run parallel with the carriageway for a while, these were great for splashing light in to those gaps between columns. They seem to use a smaller, flat lantern these days, but I think they've done their research first as it's still much more 'floody' than others I've seen around and about.

Meanwhile in Liverpool, they're using things that look like they've been modelled on a Beta 5 SOX head, and for main roads, a 1960's fluorescent tube. These are great for throwing light every which way, but as a result are quite glaring to the driver.

In a 'why fix what's not broken' approach, given the development in technology, maybe a Chip-on-board (or COB) LED or clusters of wide-angle, high power LEDs is the answer, mounted in fixture types similar to (if not the same as) we're much more use to dealing with. Assuming the lumen output was similar, the distance between columns and the spill in to premises shouldn't change too much.
Simon :driving:

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Re: LED vs SOX cut-off/spill angles

Post by Little Owl » Sat Feb 23, 2019 01:48

There is no doubt that LED is the future.

However, the real problem is that it feels like some councils just pick a random brand and model out of the hat, and then use it on all their street lights without considering the environmental context and the associated requirements.

I am sure that it would not hurt to ask the manufacturer to make the lights warmer, since many kinds of LED lighting are getting cheaper in terms of the principal and maintenance costs.

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Re: LED vs SOX cut-off/spill angles

Post by Chris5156 » Sat Feb 23, 2019 14:25

Dorman-Smith wrote:
Wed Feb 20, 2019 14:50
...strange how they have left the SOX lamps in place by the Zebra crossings, so I think from that we can read that SOX is a safer illumination maybe?
I think that's very unlikely to be the reason. I'd guess that the zebra crossings have different requirements and are scheduled for a later phase of the LED rollout.

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Re: LED vs SOX cut-off/spill angles

Post by AndyB » Mon Feb 25, 2019 13:28

Update or replacement of the zebra crossing may be pending, for example with new lighting poles with integrated belisha beacons and internal lighting for the white stripes.

Northern Lights
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Re: LED vs SOX cut-off/spill angles

Post by Northern Lights » Sat Mar 09, 2019 21:34

You are also forgetting that the higher Kelvin temp of the LED is whiter/bluer, so it causes the human eye to react like it does to daylight. Thus there is a greater perceived beam cut off, & no fade/overspill like the low Kelvin old style street lights.

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Re: LED vs SOX cut-off/spill angles

Post by Rob590 » Mon Mar 11, 2019 14:38

Stevie D wrote:
Wed Feb 20, 2019 21:56
We have had LED lights inflicted on us round here, and they're horrible. They cast a much more defined light pattern, which means that the road is well lit (there don't seem to be too many gaps but I can imagine if the existing posts were just a little further apart then there would be dark spaces between them) but anything off the road is in deep gloomth. There's pretty much no light bleed up to my front door now.
To be fair, this is sort of the aim - to light the roadway but not private property off it. While there may be some adjustment as we've got used to the wide spill of other technologies, fundamentally this reduction in light pollution is ecologically beneficial: both for the animals that live in and around human settlements, and through reduced use of carbon.

That's not to defend councils who don't properly install LED lighting - there should be constant lighting provided along pavements and roads, and crappy replacements can lead to gaps in that - but after getting used to it, this reduced spilling of light away from the roads should be a good thing.

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Re: LED vs SOX cut-off/spill angles

Post by NICK 647063 » Sun Mar 17, 2019 06:56

To be fair if LED lighting is properly installed it’s good, I use the A64 York Road out of Leeds quite often and they installed a large section with LED lighting late last year, using existing poles, these poles are quite close and on both sides as it’s a dual carriageway, I’m not sure about the brand of LED used but it looks a pretty decent type, the road it very well lit and it’s now noticeable that the road side properties are now not illuminated as before due to the height of the poles the roofs of the houses were lit up, surely this is better for the residents,from a driving point of view it’s far clearer....

I know Leeds is about to start it’s roll out this year for some reason the A64 was done before the Leeds LED roll out scheme was even approved, I have noticed comments from other areas like in North Yorkshire about people moaning their street is now too brightly lit and they can’t stop the light even with blackout curtains surely this is a little dramatic as people want well lit streets, we have had enough moaning when lights were turned off and blackout curtains block even daylight, clearly some just like to moan.

I personally like LED lighting it’s so much better than the awful orange glow we used to have.

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