just got my new bellows for my Linhof Tech III installed and am so happy, but they are not leather like the old one so the question is what is the best method for caring for my new bellows? Should I leave the camera open with bellows slightly extended when stored? Is there a treatment to be used to keep them flexible? As I said they are not leather and I don't know what they are actually made of. I e-mailed the folks at custom bellows, who made them for me< but have not recieved a reply yet.