title: "unknown revision or path not in the working tree" when trying to fetch specific commit to new directory
body: <p>Total git newbie here,</p>
  
  <p>I wanted to create a new folder that holds a specific commit I made. These are the steps I've taken:</p>
  
  <pre><code>git init
  git add remote origin &lt;ssh-clone-url&gt;
  git fetch origin &lt;sha1&gt;
  git reset --hard HEAD
  </code></pre>
  
  <p>which gives me this error:</p>
  
  <pre><code>fatal: ambiguous argument 'HEAD': unknown revision or path not in the working tree.
  </code></pre>
  
  <p>What am I doing wrong here?</p>