Exif information is not shown in TWG but the Windows Explorer does. Why?
Exif information is stored differently by each camera type. The exif reader that is used is looking at a defined set of offsets and tries to extract the information. Windows explorer (and other tools) do just know more offsets than the small php class ;). I have this problem too depending which program I use to process my images. If the images don’t work download the freeware version of cam2pc (http://www.nabocorp.com) and resize the image with the flag “copy metadata” set. Use as size a size bigger than your images if you don’t want to resize! This nice tool copies the exif data to a place the exif reader con find it ;). The exif reader is the same coppermine gallery uses. Therefore I want to thank coppermine programmers and the initial developer of the exif class who released this under the GNU General Public License!