logfile=test.log
ps_file="package1.ps"
echo $ps_file
ps_file1=`echo $ps_file| sed "s/.ps//g"`
echo $ps_file1
ps2pdf -dSAFER -sPAPERSIZE=a4 /tmp/A380_RFS24/amm_r0_ps/$ps_file1.ps /tmp/A380_RFS24/amm_r0_pdf/$ps_file1.pdf

exec 1>${logfile}
exec 2>&1


This will redirect the standard o/p(indicated by 1) and standart error ( indicated by 2) to the test.log file.