The strange part is the fact that with film - light is more translucent with a polyester base and less so thru the acetate base. Anyone have any ideas, or guesses why? No one has been able to answer this yet!! It is a very strange phenomenon. I still think that it has to do with the tapepack, but I could be wrong. Lance Watsky Preservation & Media Specialist The Georgia Archives 5800 Jonesboro Road Morrow, GA 30260 678-364-3764 (phone) 678-364-3860 (fax) [log in to unmask] www.GeorgiaArchives.org -----Original Message----- From: Association for Recorded Sound Discussion List [mailto:[log in to unmask]]On Behalf Of Edward A. Falk Sent: Wednesday, March 02, 2005 2:05 AM To: [log in to unmask] Subject: Re: [ARSCLIST] Identifying Acetate Tapes On 2005.03.01 07:25, Watsky, Lance wrote: > I was hoping that someone can tell me if the following statement is true or incorrect: > > A colleague was telling me that you can tell the difference between an audiotape that was recorded on an acetate tape, versus one that was created on a polyester base, by holding the tape up to a light source. The colleague went on to say that light will pass thru the acetate tape, whereas it will not pass thru polyester tape. They're right. You can also tell the difference by pulling on it until it breaks; the acetate snaps off cleanly while the polyester stretches first.