Canon EF 14mm f2.8L II USM - Manual (Page 8)

ENG-7
6. Filter Holder
There is a gelatin filter holder at the rear of the
lens. Cut the gelatin filter to fit within the white
frames. Then insert the gelatin filter into the filter
holder.
¡ Only one filter can be used.
¡ When you use a gelatin filter, ghosting may
appear in the image.
COP
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