help: td nested table layout question

My table with 2 td, the first td have image, 2nd td have same image but inside a table. I already setted all valign=top, but 2nd image position is still a little bit low than the first one. If I remove the table in 2nd td, everything is fine.

Anyone can tell me how can I valign them? code below:

<table><tr>

<td>image<td>

<td><table><tr><td>image<td></tr></table></td> 

</tr></table>

Thank you very much!!!
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