title: get commits since a particular date in git based on commit date
body: <p>To get commits after a particular date. I can do this:</p>
  
  <pre><code>git log &lt;ref&gt; --since=&lt;date&gt; --pretty=format:%ci
  </code></pre>
  
  <p>This seems to list commits based on author date. How do I get commits after a particular date <em>based on commit time</em> ? I can parse the output of above cmd to get what I desire, however I was wondering if there is a better way to do this.</p>