Sorry, for questioning on a closed thread.
date filter automatically converts the time from logs as per the time zone.
For example:
In log, if time stamp is '2016-09-15 09:40:24,118'
then output of date filter is '2016-09-15T04:10:24.118Z'
Please note that timezone is UTC+05:30.
I want to convert this string field to date for sorting purpose (that's why i am using date filter) and keep the same timestamp as it is in the logs .
Any help would be appreciated. 