Editing Blink comparator (section)

== Modern replacements ==
In modern times, [[charge-coupled device]]s (CCDs) have largely replaced [[photographic plate]]s, as astronomical images are stored digitally on computers. The blinking technique can easily be performed on a computer screen rather than with a physical blink comparator apparatus as before.<ref>Blink Comparator on PC http://www.instructables.com/id/Blink_Comparator_on_Personal_Computer {{Webarchive|url=https://web.archive.org/web/20200325193143/http://www.instructables.com/id/Blink_Comparator_on_Personal_Computer |date=2020-03-25 }}</ref><ref>{{cite web | url=https://skyserver.sdss.org/dr5/en/proj/user/asteroids/ | title=Finding Asteroids }}</ref>

The blinking technique is less used today, because [[image differencing]] algorithms detect moving objects more effectively than [[Visual system|human eyes]] can. To measure the precise position of a known object whose direction and rate of motion are known, a "track [[Shift-and-add|and stack]]" software technique is used.<ref>http://www.astrometrica.at/</ref> Multiple images are superimposed such that the moving object is fixed in place; the moving object then stands out as a dot among the [[star trail]]s. This is particularly effective in cases where the moving object is very faint and superimposing multiple images of it permits it to be seen better.