I have read about people using the Lee and B+W 10 stop filters, but no one seems to mention the HELIOPAN 10 stop filter, I mention this as I'm looking to buy one and HELIOPAN make a 82mm version to fit my lens, has anyone here got any experience of using these HELIOPAN 10 stop filters.
http://cgi.ebay.co.uk/82-mm-Neutral-Density-(ND)-10-stop-filter-HELIOPAN.-_W0QQitemZ250753637816QQcmdZViewItem?rvr_id=217837208969&rvr_id=217837208969&cguid=2b8b077d1250a0e204472ff7fdd4662b
http://cgi.ebay.co.uk/82-mm-Neutral-Density-(ND)-10-stop-filter-HELIOPAN.-_W0QQitemZ250753637816QQcmdZViewItem?rvr_id=217837208969&rvr_id=217837208969&cguid=2b8b077d1250a0e204472ff7fdd4662b