When Assets are served they are automatically scaled down to 430px wide. This is a bit on the narrow side but for historical reasons it's quite hard for us to change this now (since lots of sites are relying on this behaviour).

There is, however, a little trick you can do to get to the original picture, rather than the scaled down version.

Just add ?attr=image_orig to the end of the image URL. So in your example, your map image is:

http://e-voice.org.uk/friendsoflandportbottom/assets/images/landport-bottom-map

Which will become:

http://e-voice.org.uk/friendsoflandportbottom/assets/images/landport-bottom-map?attr=image_orig

This works for all images in the Assets Library (though NOT for images in the photo album etc)

Thanks

Joe