I have purchased a spare second hand polarising filter cube. The Zeiss IM microscope (similar to IM35) uses an epi-illumination system for epi-fluorescence. However it was not designed with simple bright-light epi-illumination in mind. I am hoping that I can adapt this filter cube to allow me to introduce epi-illumination in bright-field on this scope.
My first step is to remove the fluorescence filters from the cube. These are extremely expensive filters so I want to ensure that I keep them carefully and know where to put them back if I wish to put the cube back to normal. Removal of the filters is very easy – a plastic ring holds them in and is very simple to remove.
I have 3 of these filter cubes. I am not sure if they have same filters or not so I have taken photos below during removal of the filters from this cube in order that I know how to replace them in the future.
List of filters included on filter cube:
The following pictures show the cube with the filters in situ, before removal:
Removal of filters from the cube:
The two filters at front (one each side) have labels on each filter. The following photos show the labels on those filters:
After filters are removed, it is possible to see the semi-silvered mirrors within the filter cube. The following pictures show that these are them selves coloured. I do not know how this will affect epi-illumination. They may removal too much light for effective epi-illumination and therefore require replacement or allow enough light that I can leave them in situ. I can easily see through them by eye allow they do give colour tinge to view: