I'd suggest a regular expression, not tr. You probably want to do something like

  my @ImageTagList =
    ( $HTMLPage =~ m!<img src="/some/longish/path/image2002(\d+)607.gi
+f">!gi );
[download]

The g modifier looks for all occurences, and the i modifier ignores case (ref.: p.150, Camel).

--t. alex

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