[GRASSLIST:2606] Re: Moire effect in aspect map - solved

[Christof Bigler]

Hamish pointed me to the fact that the pattern could be an artifact, 
which might had been created when the original data had been processed. 
And yes, indeed, when we were zooming into the aspect map in ArcGIS, we 
could detect the same pattern. Thanks to Hamish and the others who 
helped me!
But I also have to consider that without this pattern, I wouldn't have 
detected the inconsistency beetween gdal and grass, i.e. the missing 
column and row when importing the map with r.in.gdal (see my former 
e-mails).

Christof

On 12.02.2004, at 18:53, Hamish wrote:

>> The second and original problem with the moire effect in the aspect 
>> map
>> also remains, even 1) when I derive aspect from the newly imported
>> *.e00 raster map, or 2) when I import the aspect map from a *.e00 
>> file,
>> which has been derived in ArcGIS, or 3) when I export the map as TIFF.
>> BUT, there is no such effect, when I look e.g. at the map 'aspect' 
>> from
>> the spearfish data set, which has exactly the same resolution as the
>> default settings.
>>
>> Any comments on this issue?
>
> It could be an artifcat of the original data set & processing.
>
> ?
> Hamish