The Tessina was designed by Dr. Rudolf Steineck, designer of the Steineck ABC watch camera, and distributed by Concava, the manufacturers were Siegrist of Grenchen Switzerland.

It is a well-designed and well-built precision camera directed at the increasing interest in sub-miniature cameras. It is unusual in being a twin-lens reflex and using 35 mm film which allowed a large picture area. The image from the taking lens is directed down onto the film, the image from the viewing lens is directed up to the ground glass screen. As the mirror will invert the image the film is reversed when printing.

The standard viewfinder is removable and can be replaced by a pentaprism or other finders. Next to the finder is an accessory shoe. The bottom of the camera carries lugs to which the tripod plate and wrist strap attach, a plate carrying instructions also attaches here.

Early Accessories

• Cassette loader.
• Pentaprism with 6x magnification (available 1961).
• 8x Magnifying finder (available 1961).
• Tripod plate.
• Wrist strap (similar to a watch strap).
• Neck chain.
• Case to fit on to a belt.
• Case with handle.
• Slide mounts.

Later accessories

• Light meter, fits to the accessory shoe and couples to the aperture dial.
• Flashgun.
• Watch, fits to the accessory shoe.
• Condenser lens to fit over the ground glass screen.
• Sports finder, similar to standard finder but without lenses.
• Filters.