Apochromatic Telescopes


When multicolor light (like white light) enters a new medium (like glass), the different colors bend at different angles. This spreading out of the colors is referred to as chromatic dispersion and means that the each color will reach focus at a slightly different point making it impossible to focus your eyepiece on all of them at the same time. Visibly, this appears as colorful ghosting with the different colors slightly offset from each other.

If the design corrects the chromatic dispersion to bring all of the colors into focus at the same point, then it is called an Apochromatic refractor. This usually requires additional lenses within the body of the telescope.


  • Better visual viewing experience
  • Better for astrophotography with color sensor camera


  • More expensive
  • Heavier due to the additional lenses
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