Lenses

Extension Tubes

Extension tubes are accessories that have no optical elements.  They are positioned between the camera and the lens positioning the lens farther from the image plane.  The farther away the lens is, the closer the focus and the greater the magnification making them ideal for optimising the field of view.

However, there are disadvantages to using extension tubes; the camera can no longer focus to infinity; the depth of focus is very much reduced; the length of the tube causes a loss of light which makes the camera less sensitive (often requiring a longer exposure times).

They are available in different lengths from fractions of a millimetre (used for back-focus adjustment of zoom lenses) to 10’s of millimetres.  Selection is usually done from a look up table.

  • Available in a range of lengths or as a set
  • Screw in-between the lens and the camera
  • Ideal for optimising the camera field of view/working distance

Models Available

  • Extension Tubes
  • Euresys
  • IO Industries
  • Basler
  • FingerLake Instruments
  • Moritex
  • Imperx