[Gvsig_english] BUG: gvSIG 1.9 (Build 1253) Image Filtering

[Simon Cropper (Botanicus Australia Pty Ltd)]

Jorge Gaspar,

That is a good site. It explains CRS well, but leaves out the projection 
element. It would be good if the SRS concept with projection + datum + 
coordinates are described and illustrated in tandem.

Cheers Simon

Simon Cropper
Botanicus Australia Pty Ltd
PO Box 160, Sunshine, Victoria 3020.
P: 9311 5822. M: 041 830 3437.
mailto: scropper at botanicusaustralia.com.au 
<mailto:scropper at botanicusaustralia.com.au>
web: www.botanicusaustralia.com.au <http://www.botanicusaustralia.com.au>



Jorge Gaspar Sanz Salinas wrote:
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> On 17/12/09 14:18, Simon Cropper (Botanicus Australia Pty Ltd) wrote:
>   
>> Ben,
>>
>> "Projection = a mathematical formula and its parameters that allows you to literally
>> project "natural" locations on the Earth's curved 3D surface to a plane for display on 
>> e.g. a 2D map or monitor. An approximation model of Earth's geoid shape ("Ellipse") is
>> also needed for this to work."
>>
>> OK... after you project the "natural" locations on the earths curved 3D surface to a plane what is the visual 2D representation called? Don't say projection. Whats its name? Are their multiple versions of this entity (depending on the creator)? How does this relate to lat-long? 
>>
>> Do you know of a good explanation of the "Datum + Projection + CRS = SRS" concept on the web (or can you provide one), so I can better understand the distinction between the various components?
>>
>> Cheers Simon
>>
>>     
>
> Simon,
>
> This thread (as a geodesy engineer) is quite pleasant for me but maybe
> you can point to this site:
>
> http://www.crs-geo.eu
>
> You've got there good explanations by the guys (you know, geodesic
> smart people) of what a coordinate system and a datum are.
>
> Best
>
> - -- 
> Jorge Gaspar Sanz Salinas
> Ingeniero en Geodesia y Cartografía
> http://www.prodevelop.es
> tfno: +34 963 510 612
>
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