out dashes with the -n option.  Not generated
unless specifically requested or the RequestAll API option is set)</span></span></td></tr>
<tr>
<td>Now</td>
<td class=c>N</td>
<td class=c>ExifTool</td>
<td><span class=s><span class=n>(the current date/time.  Useful when setting the tag values, eg.
<code>&quot;-modifydate&lt;now&quot;</code>.  Not generated unless specifically requested or the
RequestAll API option is set)</span></span></td></tr>
<tr class=b>
<td>PreviewImage</td>
<td class=c>Y</td>
<td class=