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Eyepiece Projection Calculator

Eyepiece Projection Calculator

One of the most common methods for increasing the magnification of a telescope for imaging the planets it "eyepiece projection". An eyepiece projection adapter holds an eyepiece between the CCD camera and telescope. Changing the eyepiece changes the magnification, as does increasing or decreasing the distance from the eyepiece to CCD (some adapters are adjustable in this manner).

Tip: The distance from eyepiece to CCD is typically in the range of 90-120mm.

Enter the original focal length and ratio of your telescope.  Then enter the focal length of the eyepiece you will use for eyepiece projection imaging and the distance from the eyepiece to the CCD chip.
Original Telescope Focal Length (mm)
Original Telescope Focal Ratio
Eyepiece Focal Length (mm)
Distance from Eyepiece to CCD (mm)

New Focal Length:  

New Focal Ratio: 

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