[Qgis-user] jumping scale

[Richard Duivenvoorde]

Hi list,

I'm trying to make it possible to print maps for people using qgis on a 
fixed scale. But that seems not possible

Eg: when I zoom to a certain extent is see:
	1:1126768656
in the "Scale"-info bottom right of mapwindow.

So i want to set it to a fixed value, say 1:1000000000

When I paste this in the Scale info indeed it zooms in, but whenever I 
pan a little, the value changes, jumpes from
1:1019086421
1:857490397
1:41862232
1:504222197
etc
just by panning a couple of 100 meters.

Tried it with data both in dutch coordinate system (epsg:28992) as with 
a simple world map (epsg:4326). Both seem to have this behaviour.

People have any idea?

Tried using the python console, and while I can get a scale(), or a 
mapUnitsPerPixel() there is now way to SET it?

Is there a reason for this?

Regards,

Richard Duivenvoorde