Two out-of-copyright maps of Ireland now available for OSM usage.

Hi,

Thanks to the National Library of Scotland (NLS), we now have two maps
of Ireland available for OSM usage.

These two maps are:
Bartholomew Quarter Inch to the mile (1: 253440) 1940
British War Office One Inch to the mile (1:63,360) 1941-43 - (G.S.G.S. 4136)

Chris Fleet, the senior map curator at NLS supplied me with high
quality scans of the above maps which I then georeferenced. These maps
are now added to their large collection of British and Irish maps at
http://geo.nls.uk/maps/ .

While my georeferencing isn't perfect, hopefully these maps should
prove very useful to the Irish OSM community as a source of
placenames, county boundaries, missing roads and spotting other gaps
in the map.

The Bartholomew maps is available up to zoom 13 and the GSGS is
available up to zoom 15. The two maps should already be available as
imagery layers in JOSM. The GSGS map should appear in Potlatch2 over
the next few days.

I've also set up a page where you can view these layers at
http://maps.openstreetmap.ie/oocmaps.html.

The original GSGS map was supplied as one image with the 76 sheets
already stitched together which proved problematic to accurately
georeference. We've recently obtained the scans for each individual
sheet so we're working on an improved version of the GSGS map which
we're planning to work on over the winter.

Enjoy!

Donal

On 8 October 2011 21:24, Donal Diamond  wrote:

> Thanks to the National Library of Scotland (NLS), we now have two maps
> of Ireland available for OSM usage.It's worth saying out loud that this is something that we have been
sorely missing in the Irish community, so Donal's work falls into the
category of stunningly awesome.

A few examples of what's possible with these maps that was difficult before:

* Tracing and/or naming rivers, lakes etc.

* Improving our county boundaries

* Fixing the locations of place nodes that were imported from GNS but
never adjusted.

* Replacing place-nodes that _were_ adjusted, but by users who have
not yet accepted the new Contributor Terms. We have, at a guess,
several hundred of these.


Just note that, as Donal mentions, the alignment is neither perfect
nor uniform, so you need to recalibrate the background imagery
frequently, particularly for county boundaries. Anybody not sure how
to do this, please ask for assistance here.

Once again, fair play!

Dermot

----------------------------------------
Igaühel on siin oma laul
ja ma oma ei leiagi üles

On 09/10/11 08:50, Dermot McNally wrote:
> On 8 October 2011 21:24, Donal Diamond<  wrote:
>
>> Thanks to the National Library of Scotland (NLS), we now have two maps
>> of Ireland available for OSM usage.
> It's worth saying out loud that this is something that we have been
> sorely missing in the Irish community, so Donal's work falls into the
> category of stunningly awesome.
>
>
> Once again, fair play!
>
> Dermot
>+1 from me! I've been waiting for ages on ebay for an ooc map of 
Longford that was 1"/mile or even 1/4 inch

For those dabblers like me who use JOSM now and then, here's how to turn 
on the maps in JOSM, took me a while to figure this out even though it's 
simple!

    * Go to preferences (F12),
    * down to WMS near the bottom,
    * in Imagery Providers tab scroll down to IE
    *   activate both of them,

They'll then be in the main Imagery menu.

Would I be right in saying that to use these to trace missing roads we 
just need to right click on the WMS layer and add a new offset the drag 
the maps so it matches up locally as best as possible?

And finally, should I be adding a 
source_ref=http://geo.nls.uk/maps/ireland/gsgs4136 or similar tag?

Thanks again,
Karl

The GSGS map is now live in Potlatch2 under the name "Ireland - NLS
Historic Maps"

see http://wiki.openstreetmap.org/wiki/Potlatch_2...
 for how to load and realign background imagery.> +1 from me! I've been waiting for ages on ebay for an ooc map of Longford
> that was 1"/mile or even 1/4 inchAnd now you have both! Glad you find them useful.> Would I be right in saying that to use these to trace missing roads we just
> need to right click on the WMS layer and add a new offset the drag the maps
> so it matches up locally as best as possible?Yes, in Josm you'll need to drag the map so it lines up with known
good ways or gps tracks. You can also save the off-set bookmark.
However the offset will change even when you pan over to a small area
so the offset bookmark may not be that helpful.

Bear in mind though that I used OSM data for many of my control points
when georeferencing so just because an OSMway and the  background map
agree doesn't mean that it is correct.>
> And finally, should I be adding a
> source_ref=http://geo.nls.uk/maps/ireland/gsgs4136 or similar tag?Potlatch2 is currently configured to use a source tag of "NLS Historic
Maps" - there's a shortcut to apply this quickly to a way - select the
way and press "b".

So in Josm, I suggest we use the same souce tag that P2 uses.

This will also allow us to monitor usage using the Irish taginfo
instance: http://taginfo.openstreetmap.ie/search?q=NLS+...

D>
> Thanks again,
> Karl
> _______________________________________________
> Talk-ie mailing list
> 
> http://lists.openstreetmap.org/listinfo/talk-...
>