signals on platforms

[deltic1989]

What people don't often consider is that signals will change their apparent intensity depending on the intensity of the ambient light. What may be dazzling at night will probably be quite comfortable during the day.

Furthermore, it's worth remembering that some signals/traffic lights may at some point during the day have strong sunlight shining upon them, making them harder to see and as such requiring them to be more intense. If I remember rightly, this caused a major accident on the GWML.

Just my two pence..

If memory serves the Ladbroke Grove crash was caused by sunlight reflecting off of signal SN109, and the driver assuming that it was at caution after a restrictive AWS indication.

 

[Railsigns]

Not necessarily. Coming the other way into Hayes (on the up) you're not directly looking directly into the beam of any particular signal out of SN300 / SN298 / SN290. Two of those signals are LED and one is still bulbs. Guess which one is more difficult to spot....

I don't deny that LED signals are brighter than incandescent lamps - they undoubtedly are - but to demonstrate that with photographs, both signals have to be viewed at a similar angle otherwise it's not a fair comparison. Colour light signals always look brighter when viewed straight-on, as hopefully demonstrated by this picture showing two identical LED signals side by side:

 

[Cherry_Picker]

LED signals are funny things. They are good in day light but come night time they are too bright to the degree of dazzling. Also in fog they seem to have little penetration compared to filament bulbs.

I disagree completely. Personally I think LED signals are better in every way than ones lit by incandescent bulbs. I don't think I have ever had a problem with being dazzled by them despite driving over routes that have used LED signals for years (and LED types make up for the overwhelming majority of signals these days) and I much prefer the more vibrant colour they emit.
I accept that this might be personal preference, and there are many different designs of LED signals out there, the ones on the Cherwell Valley are designed to "fade" as you get close to them, only leaving a small ring of vibrant light when you are really close to them, and they are very good. The fact that the LED signal is much less likely to fail is a huge factor too, it cuts down massively on maintenance as the working life of a signal is supposedly about twenty years rather than a few thousand hours which you get with a normal light bulb.

 

[A-driver]

I find the problem with LEDs is when they are combined with older types at night. Approaching balham frm streatham hill it can be easy to read through the signals as the LED ones protecting balham seem brighter and closer than the old type signal next to the streatham hill washer. And at night you have to be extremely careful which one you read.