[Talk-us] I am that MSP/St. Cloud, MN person

Apollinaris Schoell aschoell at gmail.com
Wed Oct 7 06:38:20 BST 2009


On 5 Oct 2009, at 22:07 , Mark Dalton wrote:

> I would like to bring together some newbies to experienced people to
> help everyone
> get things done.
>
> I would be happy to find a venue, supply snacks, etc..
>
> Here are some of the questions I have been asked to get a feel for  
> some
> experience that would be helpful.
>
> I will go through the FAQ's and archives to find some of the answers.
>
> Mark
>
> ===================================================
>   Some example questions I have been asked..
> ===================================================
> 1. Tag a path as a footpath. .. just
> mapped it using the photo overlay, but I'd like to use my GPS to get a
> more accurate mapping. I can see from other areas that a footpath is
> marked in orange, but I am not sure how potlatch software does this...
>
> 2. Clone a pathway. Is is possible to select a pathway and clone it
> for divided highways, or is there another method for this? I see that
> I-94 is defined, but I know there is a way to designate it as a
> divided motorway simply by defining the center of the path and then
> selecting how far apart the division should be.
>

might be easier in JOSM. JOSM has a duplicate function. But it's still  
quite some work to disconnect all ramps from one side and reconnect  
them to the cloned way. define all as oneway. revert the direction of  
the cloned way. verify and change the directions of all ramps where  
necessary. Disconnect crossing roads from the highway, add layer tags,  
bridge tags ....
check the tiger fixup wiki for some hints what needs to be done.

> 3. Joining two adjacent paths into one path. I know how to join a path
> to another, but that doesn't seem to indicate the entire path. For
> example, part of a road may have been defined as co rd 134 and another
> part defined as 3rd Ave. At one time, they were separate, but now are
> really the same road. I can join both ends together, but when you
> select one path, it is only that segment and not the entire road.
> There must be a way to select the entire road...
>

for complex editing I use JOSM. Potlatch has other strengths. Many  
mappers use both.

> 4. How do I show bridges etc. Sauk Rapids has a new bridge that goes
> over a river front road. There must be a way to show the road going
> over the other and not joining them like an intersection. Same with
> freeway overpasses...
>

you need to split the way and add bridge=yes, layer=* tags

> 5. Cutting a road in half. I know that the X button should allow it,
> but I seem to have several frustrating issues when I use that button.
> I think I am not understanding how to use it properly.
>
> 6. Roundabouts. I figured out the mini-roundabout just fine, but when
> I try to define a larger roundabout and tidy it up, it looks fine, but
> I can't seem to join it properly to other roads. Same issue as #3
> above.
>
> 7. Using GPS devices. I have a small cheap Garmin that seems to record
> my path, but how do I get it to download my recent paths into the
> computer / potlatch software? Just not sure how to do it.
>
for potlatch you need to upload a trace first and then convert to a  
way...
In Josm you can also load it and then draw a new way on top or convert  
to a way. If you convert directly you should also simplify to get less  
points. Some GPS devices record tracks already with filtering points.  
then you can use it without simplification.

> 8. Accuracy of the photo overlay. Just how sure are we that the photo
> overlay is properly syncronized with GPS precision? It seems to me
> that almost all of the TIGER mappoints were off by 30-50 feet in most
> cases. I have corrected almost all of Sartell points to correspond to
> the Yahoo photo overlay, but that assumes the photo is properly
> aligned. Is it, or did I just shift everything over too much?
> Depending upon the zoom setting, you can see some slight variaction of
> the photo overlays as well. I think a GPS device that I could download
> mappoints would confirm the accuracy of the photo overlay.
>

yes you should verify Yahoo against GPS traces. In general it's very  
good but in some areas it can be off.
Same for Tiger ways. Sometimes very good accuracy but sometimes  
completely off.
Another option is to use the Topo overlay from Terraserver. But gain  
it's correct most time but big shifts in other areas.

> 9. How do I upload a set of mappoints from OSM into my Garmin device?
> I have no idea how to do this, but would love to hear from others how
> to do it.
>

for complete maps search for mkgmap in the wiki to get a start.  
Cloudmade has some precompiled maps for download.

> 10. Other forums or other resources to answer the above and other
> questions. I am very very new to this but would like to find out more.
> Funny thing is, I drove the Google Street View car last year in the
> area, and so I am interested in getting this info as accurately as
> possible given that TIGER is so outdated.
>

The wiki is the best start. there is also a newbies list and a couple  
of other email lists. A good way to learn is also to check well mapped  
areas and see what others are mapping.
Did you record all the driving on your personal GPS? Then you have a  
great base of gpx traces.


welcome to OSM

> _______________________________________________
> Talk-us mailing list
> Talk-us at openstreetmap.org
> http://lists.openstreetmap.org/listinfo/talk-us





More information about the Talk-us mailing list