Apple Color OneScanner 600/27 - Manual (Page 151)

To insert film into the film guide:
1 Place the film guide on a clean, flat surface.
Choose the guide that’s appropriate for the size of film or transparency you
intend to scan.
2 Lift the tab and insert shutter strips into slots that will not have film in them.
IMPORTANT Shutter strips prevent overexposure (halation) of the scanned
images. If a strip of negatives is not long enough to fill the slot it’s in, that is
not a problem, but unused slots in the 35-mm and 60-mm film guides must
contain shutter strips. (The 4 x 5-inch film guide does not require a shutter
strip. You can leave one of the slots empty.) It is important not to allow any
gaps at the sides of the film. Light that shows through at the sides may cause
the film to be overexposed.
Shutter strips
143 Using the Transparent Media Adapter