Canon PIXMA MP950 User Manual page 67

(3) Close the film holder completely with squeezing it inward while pressing.
Note
(4) With the front side of the film (the side showing the correct image) face down, align the
film guide with the indentations on the right and left sides of the Platen Glass.
Note
Mounting 35 mm Slides:
(1) Align the film guide with the indentations on the right and left sides of the Platen Glass.
Chapter 4
Ensure that all the tabs on its outer edges fit into the slots in the film
guide when closing the film holder. If the film holder is floating, press
the whole downward.
If the film holder will not close properly, reposition the film so that its
perforations are set properly in the film guide slots, and try again.
When placing film strips that are shorter than the film guide, part of an
image near the open area may appear pale. In this case, place black
paper over the open area to shield it.
Labels attached to areas of the film without images may be interpreted
as images and be included in the scan.
Photo Printing from Photo or Film 65