an old Zeiss Tessar lens made by E Krauss in Paris, France
Toronto. … said Robin. Discerning camera collectors realize that Zeiss sometimes licensed its designs outside Germany to avoid tariffs – and possibly expand manufacturing capacity in the short term for photographic products.
The quarter (0.25 cents) sized Tessar F 35 f/3.5 lens at left was manufactured in Paris by the E Krauss firm under license. This lens is relatively tiny with a strange (to photographers) thread. The thread is actually an RMS (Royal Microscopical Society) standard. The RMS established the standard around 1858.
Before the RMS thread, microscope makers used proprietary threads to prevent objectives (lenses) from others to be mounted on their stands – not unlike the variation in camera lens mount designs throughout photography’s brief history.
The intent of this and similar RMS threaded lenses was to allow closeup photography through a microscope. Regular objectives have no aperture adjustment and are used wide open with the viewer ‘scanning’ back and forth to put various layers of the subject in focus.
These tiny lenses have an aperture setting to allow the subject depth of field to be adjusted . So If you should spot a tiny lens with a funny thread and a diaphragm, it may be intended for use on a microscope.
Our 2026 events are rolling out with the spring auction (May 3rd) and spring fair (May 24th) up next. The events have a poster that will be pinned a top this site close to each event date. While we can’t say you will find a tiny lens like this, we can say you will find many items to add to your collection/user gear.
