Bolex Product Code :- ????
Bolex introduced a behind the lens filter slot on the H16 Camera in 1954. Because of the differences in design in the way a Bolex cameras reflex viewing system was achieved, the effect of the behind the lens filter can be seen in the cameras viewfinder at all times. There have been four different types of filter holders designed for Bolex cameras, the type of holder you need is dictated by the model of camera you have.
By sliding off the chrome tube you will separate the two plates where you can place filter material of size 18mm x 15mm.
The SBM & EBM which both take the new larger Bayonet Mount lenses have there own filter holder which holds filter material to the size 1inch x 1 inch. This type of holder slides into the side of the camera by using the extension arm attached to it.
These new cameras are designed to carry the filter holder at all times I.E. when it is in use and when it is not required. This is achieved by sliding the extension arm into one of two position which moves the filter in and out of operation while still being attached to the camera at all times.
The EL has its own filter holder which sits between the lens and the lens mount. To get at it you have to unscrew the lens. It takes circular filter material of 40mm in diameter.
All cameras that have a behind the lens filter slot (which does not include the EL) need a filter holder to be in place at all times so light does not travel through the empty slot and fog the film. If no filter effect is needed for a shot then an empty filter holder should be inserted.