| This page
provides links to various images taken from an urban setting. It can be a
challenge to pull detail out of objects that are buried in light
pollution. Various techniques were used to pull the detail out of urban
light pollution and each is detailed in the table below each image. All of
the techniques share one thing in common in that they take sky limited
exposures. That is the individual sub-exposures are long enough so that
photon noise from the sky background is the dominant noise source. With
the subs sky limited, all that is left is to take many sub-exposures and stack them. This effectively means
that long exposure times compensate for the added noise due to the bright sky
background. It really did not matter whether high or low ISO
was used or the focal ratio as long as the total integration time is
long and each sub-exposure is sky limited. |
