I've been running into an issue with Erdas Imagine 2011. I have been creating training sites in a polygon shapefile to use with a decision tree classifier but it seems like the software keep automatically simplifying/removing points from the polygons I draw. This only seems to happen when I am zoomed in past a certain scale.
I've tried copying the shapefile and using 'Save As' to create a new copy but neither fixed the issue. New shapefiles created in Erdas do not seem to have this problem (although at one point I swear that new shapefiles were having this issue but have not been able to recreate it). I have also tried editing this shapefile in ArcGIS and it seems to work fine.
Before this started happening I had viewed the data in ArcCatalog. Could that have causes this issue? Is there some setting I am missing?
I attached two screen shots to try and clarify. I made both ellipses the same way (using the 'Ellipses' tool on the 'Drawing' tab). This is an exaggerated example but shows the issue.