[OSGeo Africa] Is a map a measuring product ?

[Chris]

    Peter ,

    Why worry ?

    IF you do not pay your eTOLL fees you WILL got to jail for six months

    The Gov will implement a special court for surveyors whose instuments are 
    a bit wonky -- and also send them to jail for six months.

    Perhaps those drawing up the legislation are just plain incompetent ?
    or
    Perhaps they do not reeally understand Jurisprudence and the philosophy 
    of law ?
    or
    the industry / profession for which they legislate
    or
    There is method in their madness and the uncertainty in the law actually 
    makes criminals out of normally law abiding citizens ?

    Take your pick

    CM




On 2 Nov 2013 at 13:07, Hanlie Pretorius wrote:

> Hi Peter,
> 
> As a disclaimer, I haven't read the bill(s) to which you refer.
> 
> Sounds llike another case of wanting to run before we can walk. What's the
> point of these bills if the actual facilities (national measuring
> standards, SABS) are falling apart?
> 
> When I started thinking about this, I realised that it's actually
> quite a philsophical question.
> 
> What I understand by the term 'measuring product' is this: If I
> measure the temparture of a bowl of water, I use a thermometer
> (instrument) and the 'product' is the reading in degrees. I can give
> that reading to a client but I have no control over how the client
> uses it. The client could write it down, but transpose the figures. So my
> measuring product is still correct, but its use has corrputed it.
> 
> A surveyor can measure a site for a client and produce a printed map
> of the site. In this case, the map is a measuring product. The client can
> use a ruler to measure a distance on the map and incorrectly apply a scale
> conversion and end up with an incorrect map product. This could be a
> 'secondary' measuring product I guess. If the secondary map product is
> used somewhere and it causes damage of some kind, the map maker should be
> able to repeat the client's action and come up with the correct answer to
> prove in that way that the primary measuring product was correct.
> 
> But virtually all maps do have errors. I can see this leading at worst to
> people not wanting to share their data for fear of being jailed because of
> the errors in their data. And at best I can see maps full of disclaimers
> about the validity of the data.
> 
> I can think of cases in which the map is the secondary measuring
> product and any measurements taken off it would be tertiary measuring
> products. If I just assemble other people's data into a map, I didn't do
> the measuring, someone else did. This could perhaps have the positive
> effect that people would be more vigilant about the pedigree of the data
> that they use.
> 
> Metrology and measuring standards use the concept of 'traceability'.
> Measuring instruments (and therefore their products) should be
> traceable to a national and then an international standard to ensure
> that 5 degrees C in Pofadder means the same as 5 degrees C in Alice
> Springs.
> 
> Would this be possible for the instuments that surveyors use to create
> maps? Can you 'calibrate' a total station? And what if the problem lies in
> the network of control points, rather than your instrument?
> 
> I'm not a surveyor, so I can't really answer these questions. Suppose I
> use a GPS to find the coordinates along a hiking path that I can't see on
> aerial images or for which I don't have erial images. I can publish that
> path on a map and, strictly speaking, it's a measuring product. But I
> don't really have any way of checking it, of making it 'traceable'. I can
> at best check it from a few control points if I'm lucky.
> 
> If I give this map to a friend with the caveat that the data has some
> uncertainty in it, should I really be facing jail for publishing this
> hiking route? I think that's crazy.
> 
> Perhaps the Bill needs to specify categories of measuring products and
> have different requirements for each.
> 
> Hanlie
> 
> > Date: Fri, 01 Nov 2013 12:27:21 +0200
> > From: Peter Newmarch <newmarch at land-surveyors.com>
> > Subject: [OSGeo Africa] Is a map a measuring product ?
> >
> > Dear all,
> >
> > Having recently commented on the Legal Metrology bill with regards
> > measuring services, I am now applying my mind to a measuring product -
> > Is a map a measuring product ? (you can certainly measure things off the
> > map).
> >
> > Also what are your thoughts about that fact that any incorrect statement
> > will be a crime - 10 years in jail. ?
> >
> > If the map (which can be considered as a statement of reality), is
> > incorrect in some way, then you would be criminally charged for this. -
> > your thoughts ?
> >
> > And lastly, if you import (presumably also download into the country) a
> > measuring product, you will need to be licensed for this else you are
> > committing a crime. In the case of say an infra red image - each pixel
> > represents a certain measuring unit or quantity of something - It would
> > be a measuring product ?
> >
> > Your thoughts on this as we need to make sure that the geospatial
> > industry gets the best deal it can get under this Bill.
> >
> > Much appreciated if people can think about this and let me know their
> > thoughts.
> >
> > Regards
> >
> > Peter
> >
> > Peter Newmarch
> > Professional Land Surveyor
> > 4Y GeoInformatics Pty Ltd
> > Tel       : +27 31 5642856
> > Fax       : +27 31 5643074
> > Mobile    : +27 82 5705859
> > eMail     : newmarch at land-surveyors.com
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