[HOT] Newbie question on digitization quality

[Russell Deffner]

Hello Peter,

 

Yes, this is the right place to address your concerns.  The tasking manager
is a work in progress and unfortunately people for whatever reason may
validate their own tasks (probably just to avoid embarrassment) and
hopefully that changes in the future.  However, don't let that stop you from
improving the data/map - you may take an additional step of contacting the
mapper who is creating 'poor' data; but hopefully they are just doing their
best and would welcome any improvements.  The only exception I would see is
if they're tagging source=local knowledge or =survey, then you probably
don't want to adjust that data to Bing; but if it's tagged source=Bing (or
no source) than you're probably safe to change.  Of course this is a dynamic
situation and in theory the map/data will need updated as new imagery or
survey is available.

 

Thank you,

=Russ

 

Russdeffner on OSM

 

From: Peter Bremer [mailto:peter.bremer at gmail.com] 
Sent: Thursday, August 15, 2013 8:00 AM
To: hot at openstreetmap.org
Subject: [HOT] Newbie question on digitization quality

 

Hi!

I am really not sure if this is the correct place to ask my question, the
HOT Tasking Manager has very little information on where to get help.

I have never contributed to HOT, and wanted to take a closer look at the
amount of work that goes into those tasks in the Tasking Manager. So I
opened one of the completed and validated spots in 
Khartoum (http://tasks.hotosm.org/job/289). But when comparing the OSM data
with the Bing imagery, I was surprised. Buildings are draw at places where
the Bing image, at best, seems to show ruins of buildings, while adjacent
structures that clearly are buildings on Bing are not draw in at all. I even
saw what looked like a dried-up river bed (complete with bridges where roads
cross over the river), but in the OSM data this was drawn as a residential
road instead! According to the history information, all elements were drawn
during the last few days.

Could the difference be based on local knowledge from the mapper? The source
attributes all point to Bing and nothing else. Did Bing just happen to
update their aerial images today? Did something go wrong when validating the
map? I am a bit hesitant to contribute, not knowing if I am misunderstanding
what it takes to create a good map. My gut feeling says the data should be
re-validated, but the Tasking Manager does not offer such functionality, and
I would feel a bit uncomfortable as a newbie criticizing the work of other
who possibly have been doing this for a long time ;-)

Thanks for any comments,
Peter Bremer

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openstreetmap.org/pipermail/hot/attachments/20130815/b0c356a5/attachment.html>