You can use nip2’s general image processing facilities to play around with reflectogram mosaics. You can make false-colour images of your reflectograms, blend them with visible images or X-rays, search them for edges, and so on see the registering and overlays_and_blending examples for ideas.
There are also some first order mosaic functions: Tasks / Mosaic / Two Points / Left to Right and Tasks / Mosaic / Two Points / Top to Bottom. These functions automatically rotate and scale the right-hand image in a join. They are useful for assembling X-ray mosaics, and for fixing very difficult joins in reflectogram images. These functions work the same way as the One Point functions except that you will need to define two tie-points on each image.
You can mosaic images of any numeric type: 16-bit integer images are handy for mosaicing X-ray images, for example.