My problem:

I have a load of MI maps that have been digitized using local coordinates
(the origin is at the corner of the page or at some other arbitrary point),
and I want to transform these maps to long/lats.

My current solution:

I allocate some control points then export each MI table as a DXF file, use
the set coordinates dialogue to set the coordinate transformation, then
import the DXFs back into MI. Unfortunately the set coordinates dialogue
only uses 2 pairs of coordinates to carry out the transformation, which is
really weak. If I want higher accuracy I go through the routine again using
2 different control points.

This is a real pain. Does anyone have any better solutions?



Also, I am looking for some sympathy / advice....I work for a mineral
exploration company in Bulgaria. Bulgaria is a place that is paranoid about
national security, and although they have the most amazing topo maps and an
excellent grid shown on those maps at all scales, the maps are published
without numbers on the grid.
Apparently it is illegal for foreigners to know the national grid. This
introduces a whole load of problems. When my company first started working
here, they used local grids for each project area. Just before I arrived
they had started digitising maps in Longs and Lats, as these can be provided
when maps are purchased, but again, in the interests of National security,
the coordinates are always shifted by about 150m, in a direction kept secret
from us.
This year, a joint venture partner insisted on carrying out all ground work
using their own nationwide metre-based grid, similar to UTMs but not the
right UTMs. At the same time we had people working on satellite images and
GPS using UTMs.................

Has anyone ever experienced such a messy set-up? The end result is that I
spend a lot of time trying to work out if things on maps are in the right
place, and then I am never quite sure how accurate the data is. Does anyone
have any suggestions / advice / consolation......I need to sort something
out for the future.


Thanks for listening.

Fraser.


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