You could try Tip #3 from the Basic debugging checklist: Check for unprintable characters by converting them into their ASCII hex codes using ord 
my $copy = $field1; 
$copy =~ s/([^\x20-\x7E])/sprintf '\x{%02x}', ord $1/eg;
print ":$copy:\n";

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In reply to Re: Invisible characters by toolic
in thread Invisible characters by lomSpace

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