Detective Camera is a camera naming category. At the end of the 19th century the name detective camera was given to hand cameras of various types.
“This is a so-called detective camera made of mahogany. It contains 12 plates of 9x12 cm. Lens...Mars Camera
“In 1886 C. P. Stirn bought the rights to make a unique kind of vest pocket camera that was...Stirn Concealed Vest Camera
“In 1886 George Eastman and Franklin M. Cossitt received the patent for their Eastman Detective...Eastman Detective Camera
“Scovill & Adams offered its 4x5in Waterbury Detective Camera, improved model, ca. 1892. The...Scovill Waterbury Detective Camera
“Emil Wünsche's Detectiv-Camera "Photo-Jumelle" was a folding variant of the popular...Emil Wünsche Photo-Jumelle