beyond macro

35mm focal length Tessar with RMS thread

Toronto. In the days of minicams (mainly 35mm),  subjects could be focussed from infinity down to about a metre. Any subject closer needed accessories like front element lenses, extension tubes, bellows, or special closeup stands.

If a lens was asymmetrical, a ring would allow the lens to be reversed then attached to possibly improve the resulting image’s flatness of field and resolution.

Macro was defined as a 1:1 film image to subject size. Macro was usually lumped in with closeups in the ‘closer than a metre’ shots. Going to larger than subject sizes on the tiny 35mm film negative required more special tools. For example, a camera could be mounted on a microscope in place of the eye-piece and the subject taken with the microscope’s objective lens.

However objective lenses had no aperture adjustment as they were used wide open. Some makers decided to remedy this by offering a special lens with an aperture to be used in lieu of the usual objective. This would allow the depth of field to be increased. Above is a tiny 35mm focal length Tessar with an RMS thread (the Tessar is shown here beside a Canadian Looney for size comparison).

Different microscope makers created a ‘line’ of lenses allowing various degrees of subject magnification. A typical shot is shown in a March 2020 post titled, “up close and personal“. The post gives added details to the 1930s Tessar which I bought back in March, 1995 from Pim Schryer (a few sources suggest such a low serial number means a far older lens, but it wasn’t until 1930 when a redesigned Tessar allowed f/3.5 lenses. Perhaps the smaller frame size needed here allowed f/3.5 with an earlier lens design.).

Savvy camera makers such as Zeiss and Leitz made adaptors to mount the tiny RMS threaded lens on traditional bellows, etc.

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