This holder also accepts commercially available gelatin filters. Even when no filter effect is desired, the gelatin filter holder must be in place because the glass filter is a part of the lens optical system.

1. To remove the gelatin filter holder from the filter slot at the rear of the lens, press the filter lock button on its top, grip its ends and lift out

1. Remove the clamp ring by pressing its upper tabs inwards and pulling it out
2. Cut the gelatin filter to fit on the folder frame referring to the illustration and place it on the holder frame
3. Replace the clamp ring to secure the gelatin filter and reinsert the filter holder into the lens. It may be reinserted in either direction and locks into place.

* A drop-in filter holder for interchangeable glass filter is also available optionally