PTtiff2psd is a utility to convert a set of TIFF files into a multi-layer PSD file suitable for opening in Photoshop or GIMP. It was written by Daniel M German. A multi-platform version is now included with the pano12 library available at Sourceforge.
The functionality is similar to Erik Krause's Photoshop stitching actions, except PTtiff2psd is a standalone command-line program.
Usage is like so:
PTtiff2psd [options] <tiffFiles>+ Options:
-o <filename> Output filename (default merged.psd) -b <blendingmode> Specify blending mode for layers (use -h to display them) -f Force processing (do not stop at warnings) -s Stack them -q Quiet run -r Reverse layers -8 Reduce image to 8bit per channel -B Force Big, PSB file format -h Show this message