Hello again and many thanks.

I did this and it looks like libtiff6 is also installed though it doesn't show in synaptic

# sudo apt-cache search libtiff
libtiff-dev - Tag Image File Format library (TIFF), development files
libtiff-doc - TIFF manipulation and conversion documentation
libtiff5 - Tag Image File Format (TIFF) library
libtiff5-dev - Tag Image File Format library (TIFF), development files (transitional package)
libtiffxx5 - Tag Image File Format (TIFF) library -- C++ interface
gem-plugin-tiff - Graphics Environment for Multimedia - TIFF support
libtiff-opengl - TIFF manipulation and conversion tools
pngtools - series of tools for PNG (Portable Network Graphics) images
python3-libtiff - wrapper to the libtiff library to Python using ctypes (Python 3 version)
libtiff-tools - TIFF manipulation and conversion tools
libtiff6 - Tag Image File Format (TIFF) library
libtiffxx6 - Tag Image File Format (TIFF) library -- C++ interface

Thank you all

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