1. Since the update of Lightroom 6, the backup from Lightroom have been created as Zip files, as the zip files consume less storage on the drive instead of backing up the complete catalog.
2. The time for backup entirely depends on the size of the catalog, if the catalog is quite big, Lightroom will take some time to backup the catalog.
Thx for th ultra quick answer
Meanwhile I downloaded 6.6 and creates again unziped version of back-up
Might be, that time differences between 5.7 and 6.5 in creating back-up has been because of the zipping effort
Best regards and thx
thx I knew this, but I do want to have a back-up
Safety first )
Right, it always safe to take a backup of the catalog.