[ATM] Depth of field

[Grey Coyote <greycoyotee@yahoo.com>]

Does anyone remember the equations for calculating the
depth of field?

Does anyone know what the f ratio changes to when
adding an eyepiece and its aperature?

Ex. Compare a 5mm eyepiece magnifies to 150 on a 750mm
focal length vs the 150x magnification by a 12mm
eyepiece at 1800mm focal length. What I am after is a
near estimate of what the depth of field will be for
the eyepiece at 12mm by 1800mm focal length.

Course the short answer is does anyone know if a
larger diameter eyepiece is going to have better depth
of field than a smaller diameter eyepiece? I'm after
improved focusing.

Thanks!
-Rob

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