Hi, I'm using a code which creates a new field by assigning values to individual cells. If --in the middle of the script-- I create a projected image, the new field gets wiped. This script demonstrates the problem: http://paste.yt-project.org/show/2517/ Here, the code loops over two objects, and gives their neighbouring cells values in the new field and creates an extracted region from those cells. When the second object is called, the code reassigns its cells to object one and creates a new extracted region of object one's cells. If line 53 is not called (p = pc.add_projection("Density", 2)), this is fine. Both objects initially have 26 cells and then object one gets 52 cells. If the projection is created, the code forgets about the cells it assigned to object 1 in the first loop and object 1 ends up with only object 2's cells. This isn't a huge problem for me, since I can just ensure I never call a projection during my script. But.... I am liable to forget and clobber my data at a later point! Is it easy to somehow bank the new field so it's not destroyed during a projection? (If not, no worries.) (Matt, I know we previously discussed how projection didn't know about the new field. Possibly, this is a logical consequence from that and if so, I'm sorry to repeat the question!) Elizabeth