HåkanC skrev:
-------------------------------------------------------
> geologen skrev:
> --------------------------------------------------
> -----
> > En rund ljusbild är nära optimal för cykel.
>
> Vi som har mer erfarenhet vet att det finns
> bättre ljusbilder för cykling.
>
http://swhs.home.xs4all.nl/fiets/tests/verlichting
> /lichtbundel/theoretisch/thumbnail/symmetrische_li
> chtbundel.gif
>
http://swhs.home.xs4all.nl/fiets/tests/verlichting
> /lichtbundel/theoretisch/symmetrische_lichtbundel.
> gif
> "So, a fairly large amount of light is wasted (for
> road use) by circular beams. But not just that:
> while a symmetric beam may put about 0.60 - 0.70
> of its light on the road (well, more accurately on
> spots below the horizon, and a lot beside the
> actual road), that doesn't mean it's as good as a
> lamp with cutoff that produces the same amount of
> light as that 0.60 - 0.70 of the symmetric lamp.
> This is very clear from my comparisons of the
> Magicshine MJ-808 and Ktronik's triple dynamo
> powered XP-G with an Edelux. The Edelux is much
> better due to its even beam and longer throw. It's
> also brighter on most parts of the road that the
> Edelux's beam covers
> ...
> I estimate that a symmetric lamp must have ca. 3
> to 4 times the power of an asymmetric lamp with
> cutoff, to light up the road as well (as useful)
> as that lamp with cutoff.
>
> As to being able to see traffic signs etc., you
> don't need a circular beam for that, lamps such as
> the Edelux give plenty of spill light to light up
> traffic signs when aimed below the horizon."
> Läs själv här:
>
http://swhs.home.xs4all.nl/fiets/tests/verlichting
> /index_en.html#licht-bundel-vorm
>
>
> /Håkan
Japp. Då blev det ordning i klassen. Ljusguden Ra har talat ;-)
