The problem -  inability to make some lines, nodes , points fall where they
should / I want them.  It all started when I couldn't get a point object
placed at the centroid of a Poly Line by copy/paste the centroid X_Y numbers
for the line to the points X-Y numbers (trying to get calculated  1/4
corners on township section lines).  The points were off by as much as 30
feet.

After reading many postings, the 5.5 docs and Jacques Paris's books.  I've
created a new coord. Sys by copying and pasting the State Plane NAD 27
Michigan Southern Zone (the projection of most of my base tables)- adding
the proper numbers (2000 to create a bounded system) and coordinate bounds
for the county we are in.  Precision just increased by 2 decimal places, and
I am a happy camper (precision-wise), points went to within .0001 feet of
Pline centroids.

Here it is: "Michigan 2113, Isabella Co in the Southern Zone (1927)\p26790",
2003, 73, 8, -84.3333333333, 41.5, 42.1, 43.6666666667, 2000000, 0, 1800070,
715923, 1928000, 844552

FYI - the first number after the quotes was 3, you add 2000 to this to make
it bounded = 2003, the last four numbers are the X1 Y1 and X2 Y2 coordinates
for the bounded area.  To get these, create a region with the square region
tool and get its coordinates by dbl clicking on it.  Copy and paste the
coordinate definition you want to base it one, add a unique name to the text
in quotes ( I added "Isabella Co in the" to what was there), add the 2000
and the bounds.

Now, I just need to know if I change some or all my table projections to the
tighter precision, am I going to run into any unforeseen problems?  Some
ones I've imagined are - sharing data with others (would it matter if they
were inside or outside the bound area?, do they need to have the new bounded
projection in their .PRJ file too?), mixing the two projections (should the
conversion be all or none?)

One other concern, should I seek to create bounds that share the LCM (Least
Common Multiple) of the larger bounded area.  I ask this because Mr. Paris
shows in his book that mixed projections create a grid that contains only
the shared points.  Should the coordinates of the bounds be coordinates that
are also part of (fall precisely on) the grid for the larger projection?

Ps- It has occurred to me that I cannot import other data that is outside of
the bounded projection into the mapper if it has the tighter projection for
the map window.

Any / all comments appreciated.

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