On Thursday 08 August 2013 15:35:03 Nick Leverton wrote:

> The settings that affect this are in Control Centre / KDE Components /
> File Manager.  There is a tab titled "Previews and Meta-Data" which has a
> setting for the maximum filesize that will have a preview generated when
> browsing in icon mode, and another denoting whether to use an image's
> embedded thumbnail (if any).  You can also select which access protocols
> will use previews, so that you don't accidentally preview large files
> over a network.

Thank you for the help, but as I had written I did check these. Maximum file 
size is set at 100MB and the pictures are under 6MB each (compressed). They 
are stored localy, and other software can show them and create thumbnails.

kview and Gwenview don't seem to be able to display the pictures. Only Xfce's 
ristretto image viewer does the job.

Thierry