See if this helps:
// requires JMP 14
// on a virtual machine, the network drive F will process
// around 50K files per minute this way
mfi=Multiple File Import(
<<Set Folder( "F:\MandelbrotTrace\pics" ),
<<Set Name Filter( "*.jpg;" ),
<<Set Name Enable( 1 ),
<<Set Size Filter( {50000,100000} ),
<<Set Size Enable( 1 ),
<<Set Date Filter( {2019-01-01, 2019-01-03} ),
<<Set Date Enable( 1 )
); // note: no import is performed with the <<import method.
// the 3 filters can be respecified for nearly free
// as long as the folder isn't changed and mfi object
// isn't closed.
mfi<<Set Size Filter( {50000,300000} );
mfi<<Set Date Filter( {informat("2019-01-02T08:41:32"), informat("2019-01-02T08:43:52")} );
// make a table of selected files
dtFiltered = mfi<<showSelection();
// make a table of rejected files
dtUnFiltered = mfi<<showRejection();
50K/minute for this configuration of a network
Columns include filter values
Craige