how to publish topics while using messagefilter?

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Hi, I am using an LRF and a servo for my application and need to synchrnize the position of servo and laser data in time. I looked into message_filter and trying to play with it. I was wondering whether ApproximateTime synchronizer publishes on any topic or if not then how to get the data to publish in user defined topic? I looked into quite a few previously discussed answers on this issue here, but could not understand this part.

I need to access the synchronized dataset for servo and lidar.

thanks,