Tim
Based on the code in the referenced KB article above, using filename = str(item[1]) should only include the original filename of the attachement/photo.
It might have been changed, but previously photos were attached with a name like Photo1, Photo2, ... etc, repeated for each feature. If that's still the case, then you may find that your attachments with the same name are overwritten and you need to use a prefix to overcome this.
I hope this helps.
