Acer Film Scanner - Manual (Page 21)

English
11
If you want to scan slides:
You can use the slide holder (the holder with 4 rectangular lattices
and a SLIDE mark) to place your slide.
Slide holder
Pull the handle on the cover to open the cover.
Then place the slide on the slide holder with the emulsion side face
up. When you place the slide in the lattice, insert the lower left corner
of the slide into the plastic stopper, then push the slide into the lattice
until it is firmly fixed. You can place up to 4 slides in the slide holder.