I have a 3400x4303 JPEG and when I try to export it as a rotated georeferenced TIF the TIF that is 509x578.
Because the TIF is rotated I don't expect the resolution to be the same but I certainly don't expect it to be smaller.
In the Export dialog I can manually set the Raster Size but can't ArcGIS just autocalculate what the new raster size ought to be if the resolution of the source image is to be maintained?