[OSM-talk] Some observations from a newcomer

[Christoph Eckert]

Hi David,

thanks for your thoughts:

> I've recently joined in doing some mapping. I thought I'd share some
> observations. Though I'm new to this project, I do consider myself
> technically competent.

The same is valid for me. Being a bloody n00b to osm (six weeks or so), 
I also wrote an similar email to this list which triggered a huge 
thread. The subject was "[OSM-talk] N00b experiences" and the initial 
message was sent 20060903.

[...]

> - Sorry to start with a damning criticism, but the viewer on the home
> page is completely useless. It can leave it 20 minutes sometimes and
> never see either the landsat images or any data plotted, or sometimes
> just a small part.

During the thread mentioned above all agreed about that, even the 
developers. But please be polite and don't blame someone if he tries to 
do something good and the project fails. There's currently work in 
progress which probably will replace the current applet by something 
much better. This kind of progress usually is called evolution :) .

> The edit applet is the only way I can look at 
> existing data (from the web site - obviously, I could use JOSM).

I have learned that it is much better to use osmarender to look at the 
areas I just mapped. Disadvantage: Segments are not enough, you need to 
create and tag ways at first.

[...]

> - A lot of areas seem to have segments, but virtually no Ways (and no
> street names). This seems like wasted effort as if you don't know the
> street names, it needs a second survey to pick them up. I found I
> needed to put the names I collected into the map soon after surveying
> (even if I didn't upload it immediately), or I'd forget the nuances.
> Main roads form a useful skeleton, but recording the closes and
> avenues of a housing estate without adding the street name data (and
> hence the Ways) seems pretty pointless to me.

I disagree. I collected a lot of tracks, loaded them in JOSM and have 
drawn segments. Then I thought I will leave it up to other people who 
want to contribute to create the ways of the segments. This has some 
advantages:
* Other contributors may not have a GPS at all or at least one which 
cannot collect tracks. Such users may be interested to get a free map. 
If they are familiar to a region I segmented, they can enter the 
streetnames easily.
* This way I have more spare time to collect tracks, even down to the 
level of footways. This means more details collected.
* Tagging ways can be done later, maybe during the cold and dark winter 
months where biking isn't that much fun
* Concerning lacking details, osm is like a wiki and constant work in 
progress. I try to collect as many details as possible, but if I miss a 
footpath, somone else can add it later.
* The only reason why I started tagging myself is that I wanted to see 
the result of my work via osmarender. That's why some street names are 
lacking and why I didn't care much about the various nuances of 
highway-tags

> - I tried photographing street name signs, but it was too fiddly
> turning camera on and off (and wasn't helpful in the dark), and I
> decided in the end sketching a map, tube-style, as I went round was
> easiest.

I never use a cam because I prefer biking over taking pictures. Most 
streetnames I entered have been taken from my mind, but OK, I'm very 
familiar with my home town.

> - I had to cover some ground twice, just to get to virgin territory,
> and I was surprised how much the GPS traces varied. Even when it said
> 6m accuracy, I'd find I'd got a parallel track to the previous day
> Fthan 6m away, and it wasn't just being on the other side of the
> road.

That's the GPS receiver who fails and this behaviour is normal. If it 
drives you nuts, try one of the new SIRF-III based devices.

> - A question: I've got a railway going over a bridge over a road, but
> it shows up going under. How do I force the railway bridge to be an
> over-bridge? And can I, with the railway as a single Way, put it over
> one road and under the next one it crosses?

AFICT osmarender currently simply puts major roads over minor roads, 
ignoring any level tagging. But there have been some ideas about 
tagging such things recently. Search the list archives (are there 
any?!?).

> - I sometimes wanted to mark the position of a roadside feature (e.g.
> Church, filling station). Waypoints are fiddly to enter, and I found
> the easiest way in the end was to mark the name on my sketch map,
> and, as I was on a bike, just loop around on the road so I got a
> little circle on my tracklog.

I do not enter waypoints as well. It only wastes time. Rounding it by a 
track circle or cross is the way I do as well.

> - Why does osmarender do trunk roads in red and primaries in green?
> This is the reverse of the convention usually used in the UK. Maybe
> other countries are different.

I bet you can tweak it via the stylesheet.


Cheers,

ce