Wayne,
If I am printing a landscape format image, w/ horiz. format set in Page Setup, I have right and left margins set at .13 in LR. I'll pull my cell size in from there, to establish an image width in the print of 21.5", centered. When the image prints, however, the image width is coming out at 21" (or so), with the image cropped off the at right side, and an extra margin on the paper where the crop occurred, so the image is not centered as it should be.