The user manual for my Minolta XE-7 explains that, when using an Auto Rokkor lens, the lens should be kept in the stopped-down mode when the shutter is released. I have tested my Auto Rokkor 100/3.5, and the diaphragm clearly stops down automatically at the time of exposure. I tested it at slower speeds, 1/8 and 1/4, so that I would be able to identify the action of the diaphragm. I also used a smaller aperture, f/11, I believe. I would think the authors and/or technicians would have tested this. Perhaps my lens is a later "Auto" version that, with the XE-7, does not require stopping down at the time of exposure?