ImageMagick is a raster processor. So any vector file such as EPS will be rasterized. Imagemagick cannot re-vectorize it. So the raster file is only put into a vector shell. Thus, ImageMagick is probably not the tool you want, if you want to go from vector to vector.
See
http://www.imagemagick.org/Usage/formats/#vector
The color reversal is likely due to test.eps being CMYK. So try
Code: Select all
convert -colorspace sRGB EPS:test.eps -resize 800x800 test2.eps
Red coloration differences are probably because your original contains spot colors and ImageMagick cannot handle them.
Note that pure vector images have no size. They are controlled by density when printing. What you are doing is converting the vector image into a raster image at its default density, resizing it and putting it back into a vector shell. I do not see the point of doing that with ImageMagick. You might as well just convert to JPG or GIF.