Interesting lighting site

[SA_SA_SA]

The following highly technical site is interesting, although I am suspicious of some of his maths and his views on rear lamps seem biased to the effects on close following cyclists hence he seems to prefer a dim rear filament bulb to a brIght led, although
he might have a point about a diffuse source being easier on following cyclists. (I always though duracell rear lamp looked more visible than the Never ready nightrider even though the latter was 5 times brighter in the centre).

http://swhs.home.xs4all.nl/fiets/tests/verlichting/index_en.html

[meic]

I think I agree with you about the rear lights and I dont quite see eye to eye with his views.

But possibly I am considering the wrong scenario. I am imagining a car approaching from a long distance behind with frequent (if not consistent) chances to see your rear light. In that circumstance they are going to see your light regardless of which one you have (if they are looking out of the car), possibly we should be investing more in our lights ability to be seen from other angles more easily, a car approaching you from the side is probably going to have much less chance of seeing you in time.

I have an old Eurolight which is excellent from miles behind and carries a BS stamp but it rapidly loses its effect as you move to the side. My Smart 7 LED has two of its LEDs pointing sideways.

I agree with him about blinding other road users behind you and I try to have my bright blinky on only when it is beneficial ie I am alone or at the back. Other times it is just a moderate rear light but I always have two lights fitted on those occasions.

[robc02]

I read it a while ago and had the same doubts about his views on rear lights. However, he does try to be objective and explains his opinions so you are able to make allowances if you disagree with his reasoning.

[Brucey]

do we know what kind of accidents happen at night, and how any changes in lighting might influence the chances of them?

BTW the views on that site are (IIRC) heavily skewed towards those conditions whch prevail on Dutch cyclepaths; specifically;

-there are often lots of other cyclists on the paths, and potential annoyance to others (following or oncoming) is a significant issue.
- the main front light is 'in competition' with car headlights which can cast shadows over the path surface itself, and cause blinding (e.g. when the cycle path goes through an underpass or is sunken below road height cyclists get blinded by nearby headlights even on dipped beam).

My view is that his idea of an 'adequate-to-see-where-you-are-going' headlight is about x2 or x3 better than I have found adequate on unlit country roads in the UK. Maybe 'more is always better' here, but if so, we are getting close to the point where we will need main and dipped lights.

BTW my view is that reflectors have a lot going for them, and that there are better reflectors for bicycles than traditional ones. I used to commute on a silver-coloured bike, and I had strategically positioned 1cm x 2cm patches of reflexite material on the bike, of the kind used for making white backgrounds on road signs. In daylight you would have to look hard to see them at all but at night they stood out fantastically well, about x2 or x3 more bright than standard reflectors, I'd say. They weighed next to nothing, too.

cheers

[SA_SA_SA]

Yes, he did seem rather fussy about front lamps.

Rear lamps: yes on a separate cycle path any rear lamp should do, but

From a distance even if light source takes the whole width of the lamp, it will still need to from a (truncated) cone to be visible from off-axis; I haven't noticed the effect of LEDs becoming dimmer as they recede, I just notice them being effective compared to car lamps, as opposed to the feeble filament lamps of the past.

The one time I was uncomfortable due a preceding cyclists rear lamp, he was using a filament lamp with (presumably) a large halogen bulb in it rather than the original bulb: that made me want to screw my eyes up, no LED lamp has done that.

[[XAP]Bob]

I get blinded by DLRs and "dipped" headlights, even when I'm driving an MPV.

I put dipped in quotes because most people put them as high as they'll go, which is inevitably several feet above the horizon.

[rootes]

think side illumination / visibility is the main thing missing from cycle lighting generally.