[Tagging] Tagging road illumination quality

[Volker Schmidt]

I am very cautious about any of this kind of measurement for the following
reasons:
1) the results will be very difficult to standardise
2) the effort is far beyond that what a mapper can reasonably do.

If you wanted to do it properly you needed to mount a measuring device in
such a way that it looks downwards to measure the reflected light, may be
on some kind of arm protruding from your vehicle (bicycle in my case) and
then record continuously the measurement. Now you have to consider the
parameters:
measurement device characteristics
distance from the ground
weather conditions (we would need to define "standard dry weather", because
with rain you will have the problem of direct reflectosn of light sources)
signal integration parameters (do you average over 10m for example?)
and most likely others.

Then you still have the problem of how to define the illumination quality
of a stretch of cycle path. Assume you have a 100m stretch with nice
illumination but there is a tiny S-bend exactly overshadowed by an
evergreen tree, which produces a pitch dark spot of 10m at a dangerous
point. What do you do? Put an illumination value every 5 meters or, and
that's what I would do, mark the entire 100m stretch as lit=very_poor (or
something similar).

Constructive and realistic suggestions are welcome.

Volker

On 18 January 2015 at 11:34, Warin <61sundowner at gmail.com> wrote:

>  On 18/01/2015 5:14 PM, tagging-request at openstreetmap.org wrote:
>
> Date: Sun, 18 Jan 2015 00:14:36 -0600
> From: "John F. Eldredge" <john at jfeldredge.com> <john at jfeldredge.com>
> To: "Tag discussion, strategy and related tools"
> 	<tagging at openstreetmap.org> <tagging at openstreetmap.org>, Volker Schmidt <voschix at gmail.com> <voschix at gmail.com>
> Subject: Re: [Tagging] Tagging road illumination quality
> Message-ID:
> 	<14afbadb528.27a5.8c042f3e6e983dd0f57452e62f7f805b at jfeldredge.com> <14afbadb528.27a5.8c042f3e6e983dd0f57452e62f7f805b at jfeldredge.com>
> Content-Type: text/plain; charset="utf-8"; Format="flowed"
>
> You could use a light meter to measure how bright the light is. That isn't
> the only factor in the suitability of the lighting, but it is objective.
>
>
> My 'smartphone' can give a light reading -Andriod using app 'GPS Status'
> in lux or foot candle. There should be others that do the same kind of
> thing. Uses the camera function to determine the light from the exposure.
> But 'we' will need guidance on how best to measure it. Possibly pointing it
> at the ground immediately under the light for a hi reading, and anothe
> midway between two lights for a low reading and take the average? Maybe a
> google will turn up some ideas? The phones won't be accurate but should be
> good enough for an indication.
>
>  --
> John F. Eldredge -- john at jfeldredge.com
> "Darkness cannot drive out darkness; only light can do that. Hate cannot
> drive out hate; only love can do that." -- Martin Luther King, Jr.
>
>
>
> On January 16, 2015 11:18:33 AM Volker Schmidt <voschix at gmail.com> <voschix at gmail.com> wrote:
>
>
>  > I would like to enter illumination quality for bicycle infrastructure> (cycleways) in OSM.
>
>
>  > Any suggestions welcome>> Volker
>
>
>
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