[OSM-talk] New Popular Edition in JOSM

[David Earl]

> -----Original Message-----
> From: talk-bounces at openstreetmap.org
> [mailto:talk-bounces at openstreetmap.org]On Behalf Of Nick Whitelegg
> Sent: 12 November 2006 11:11
> To: talk at openstreetmap.org
> Subject: [OSM-talk] New Popular Edition in JOSM
>
>
>
> I would like to announce the addition of New Popular Edition
> support to the
> landsat plugin in JOSM.


This is excellent again, thank you.

But now I'm a bit worried. The tracks in my area don't align. (And no, it's
not changes to the street pattern!) If I move the NPE maps to align on a key
point, then they quickly diverge in all directions from the point. Most of
the nodes are mine, but not exclusively, and mine have always joined up with
other people's in my area remarkably accurately. The River Cam was traced
(not by me) from Landsat, and taking into account the Landsat translation
which I've now mostly corrected, that doesn't match either.

I *think* it is nearly all scale (at least in a small local area), not
rotational. It's nearly all (though not completely) a North-South
difference, amounting to maybe 50m in 1500m, but the north-south divergence
gets greater the further east of west you look from the point as well as
north or south, i.e. while the difference is mostly a vertical misalignment,
it gets worse the further you go in *any* direction.

(The grid squares on the NPE layer are also elongated vertically)

Should I be worried about all the data I've entered? Can I use the NPE layer
for anything useful with any confidence?

David