I've visited a photoschool, a professional lab and others. And I'm very disappoi nted.They are not very cooperative in letting me use their transmission densitom eter; belief me that is an understatement. They probably think I want to steal something.By the way I also told them that a reasonable fee would be acceptable. Nevertheless I heard that you can measure t he negs using a spot meter. If that's trough how does it work. Where can I find information about alternative measuring methods instead of using a densitometer.