You cannot really sync the two iPhoto Libraries on your Mac and iMac using PhotoStream. The Photo Stream can auto import the new photos added to the stream from any of your devices, if you enable auto import, and you can automatically upload your new photos to the stream, if you enable automatic upload. This is limited to the most recent 1000 new photos.
But the photo stream will not reflect your adjustments and edits, unless you add the edited photos again manually to the stream.
If you want to share specific events, you might consider to use shared photo streams to import from:
If you really want identical libraries on both your macs, copy your iPhoto library to an external disk and plug this into the mac you are currently working on.