[OSM-talk] Bing maps is misplaced

[M∡rtin Koppenhoefer]

2010/12/19 Steve Bennett <stevagewp at gmail.com>:
> On Sun, Dec 19, 2010 at 11:04 PM, M∡rtin Koppenhoefer
> <dieterdreist at gmail.com> wrote:
>> This discussion is simply about the quality level: are you satisfied
>> with probable information derived from an aerial photo depicting the
>> situation some years ago, or do you want to insert only information
>> you verified on the ground and you can guarantee for?
>
> Ah, cool. For me, this is a no-brainer: very comfortable with
> "probable" information. I'd rather have 1000 streets at 90% accuracy
> than 10 streets at 100% accuracy. Yes, that means I've created many
> errors in OSM.


yes, in you example you would have 100 wrong streets. I'm not
believing your numbers btw.: I doubt that you can only visit and map
10 streets with the effort you have to put 1000 streets from
orthofotos (1%). Even if this ratio was only 10% (in my experience
mapping takes as long as surveying, which would result in 50% for no
survey at all) I would prefer 100 reliable streets to a thousand of
which a hundred are wrong. If there is no information, this is at
least reliable in the sense that you know you can't rely on it ;-)


> Btw, no idea how a ground survey would give a better idea of
> highway=tertiary vs residential.


agreed, this requires actually not one ground survey but good
knowledge of the area.


Also, all suburban streets (of which
> the example was clearly one) are access=yes, no question there.


OK, so you do have good knowledge of the circumstances/surroundings,
which is important. To explain myself: I'm not against mapping from
aerial imagery, I do it myself, but there are limits. A very good map
can't be done just from orthophotos.

cheers,
Martin