This Leitz modulopak vertical illuminator has the standard 42mm diameter annular dovetail change ring for attaching to the top of microscope stands of the generation that included, most notably, the Ergolux, Secolux, and Laborlux ME and HL. The upper housing includes a 1x infinity corrected tube lens and the mounting ring for the viewing tube. This illuminator must be used with infinity corrected objectives.

The central ‘brick’ contains a fixed Gauss beam-splitter for brightfield work, as well as an annular fully reflecting mirror for darkfield (both are on the same substrate glass so alignment is assured). This modulopak is an earlier version so the Gauss mirror does not have the special dichroic coating that enables the attachment of the laser autofocus system. Above the mirror is a horizontal slot that accepts filter sliders, including analyzers for polarized light applications and interference contrast work (no filters are included). In the base of the housing is an annular condenser lens that is used when the darkfield method is employed. This ring focuses the light to a point somewhat above the objective lens turret where it then opens up into a cone that enters the top of the objective at an angle. This clever adaptation allows the design of darkfield objectives using standard RMS threads but it does mean that the distance of the objective from the illuminator is critical.

The illumination tube includes a recess for 35mm diameter mounted filters as well as a collector and relay lenses and three additional slots. The largest slot accommodates an included ‘V-Slide’ which has a precentered adjustable aperture diaphragm and a centerable adjustable field diaphragm. When the entire slider is moved to the alternate position a special darkfield system is engaged. This moves a central stop into the light path so the annular lens is then illuminated.

The second two slots are for an optional polarizer (for interference contrast applications) and a first order red compensator, also for interference contrast. Neither of these optional components are included – the original blank covers are present, however.

This illuminator (Leitz catalog number 563 486) is in perfect condition. The only marks on it are from a fiber optic adapter that was clamped onto the extension ring at the back of the illuminator. All optics are perfect and all adjustments work properly.

***MPN 563 486
***OEM Leitz
***SKU*** 21585

This is a rather unusual optic manufactured by Gamma Scientific. It came in a small plastic capsule with the label as shown in the third photo. (The capsule had urethane lining which had deteriorated beyond recovery and had to be discarded – hence the stains on the label which was inside the capsule).

It appears to be a standard type of 10x microscope objective of the shorter adjustment length (37mm). The shroud that would have carried the nomenclature has been replaced with a special shroud that has a pinhole and is optically deadened with a flat black finish.

It is identified as a ‘photometry objective’ which would explain the black shroud. The pinhole is located at the focal plane of the objective which indicates this was focused on an aerial image. The pinhole very accurately defines an absolute area for light integration.

The objective is in excellent condition.

Photo set 1555
***MPN 700-10-7
***OEM Gamma Scientific Inc
***SKU*** 21577