[Qgis-user] jumping scale

[Carson Farmer]

Richard,
>
>> This behaviour is normal if the project works with an unprojected CRS 
>> such as the default WGS-84, because the scale differs in each point 
>> of the canvas. The canvas would has to be re-zoomed while panning to 
>> keep the fixed scale. But isn't.
>>
>> However the problem doesn't concern projected CRSes, so just set your 
>> project CRS to any (say the Dutch 28992), enable on-the-fly and the 
>> scale should remain fixed.
>
> I tried to set up a project in epsg:28992 and load a shape in 28992, 
> but still have 'jumping scales' (though it indeed looks like in the 
> North-South direction the jumps are much larger then in West-East 
> direction).
>
> Should I file a bug for this?
I still don't think you should file a bug, as epsg: 28992 is an oblique 
stereographic projection. This means it is a conformal projection (i.e. 
it preserves angles). It does not preserve distances or areas, and so 
the scale will vary. You are best to use some sort of equidistant 
projection.

Carson

-- 
Carson J. Q. Farmer
ISSP Doctoral Fellow
National Centre for Geocomputation (NCG),
Email: Carson.Farmer at gmail.com
Web:   http://www.carsonfarmer.com/
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