> after John's emails I'd like to be sure about a couple of things. > 1- What matters for flipping is the handness of storage, is that correct? Yes. > 2- Data stored in Right hand system needs not to be flipped, while Left > hand stored data need to be flipped.? Yes. > 3- To tell the handnees of the actual > data, John suggested to look at voxel (1,1,1) for axial images. Now if > voxel (1,1,1) is LPI my data are right hand and need not to be flipped in x > dimension. is that correct? Yes. > If voxel (1,1,1) is RPI data need to be flipped > in x dimension. is that correct? Yes. > thanks for any help That was easy. best regards, -John