[Qgis-user] Creating Geological Maps

[Gerhardus Geldenhuis]

Hi
I am very new to Quantum GIS and the learning curve is a bit steep at
present but I believe worthwhile. I will much rather do the work in Quantum
GIS than work on a map in Illustrator.

Here is what I am trying to do and having difficulty with:
I spend a few weeks in the field creating a paper based geological map which
is on a number of transparent sheets which I have scanned in
and aligned properly. These maps where done on a 1:10000 scale and using UTM
WGS 84 grid co-ordinates to make mapping a bit easier. I now want to
digitize these images into a vector layer which I believe is the most
appropriate. I also want to add Google earth and other source images.
I also have a number of gpx files generated by my GPS which is another layer
I want to add.

My first question is with regards to the png images that I am using. When I
add these images as a raster layer they appear very dirty and when zooming
in the detail is obscured as if someone has rubbed over it. At first I
thought that the issue was jpeg compression which took away detail so I
resaved the images as png files and double checked using various image
viewers under Ubuntu that the image quality is up to scratch. So for some
reason Quantum GIS is not displaying these images correctly how do I fix
this?

Second question is how can I "align" this png file with with an actual
co-ordinate system. I have marked 4 points on my paper maps and lines
between these points that represent the UTM grid on which I worked and I
would need to at least roughly align this image with the UTM grid.

Thirdly I am not sure how to draw on a new layer but still view my image as
a template for the digitizing.

I am more than happy to read any documentation and work through tutorials.
What is lacking at the moment is the terminology to search for the correct
things and experience. I am working through a number of tutorials but are
still struggling a bit to connect A to B.

I will eventually add some ASTER imagery but it is my understanding that
these are in tiff format and contains extra information like spatial
referencing. I suspect that if I can master the above then adding ASTER
imagery will be easy.

Lastly is there any geological map symbol databases available?

I would appreciate any pointers or brief/detailed outlines of the
methodology I should be following to get best results.

Best Regards

-- 
Gerhardus Geldenhuis
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