FlySpanker Blink Comparator

Science-inspired fun!  The FlySpanker Blink Comparator brings classic astronomical "plate blinking” techniques to your iPhone.  With this App, you can easily upload two photos taken of the same scene, preferably in quick succession, and align them with each other.  When blinking between the aligned images, any foreground differences are highlighted, typically to comic effect.  For example, we typically allow our children to take "silly" pictures as long as they are able to take a "serious" one first; the Blink Comparator will make an animated image of these two pictures to highlight the differences.  After image registration, the App will save an animated image to your photos.  You can choose between slow and fast blinking.  The registration effect works best with minor changes (offset and rotation) to the background scene.

Fun Facts: In early Astronomy, the "fly-spanker" was a glass plate with reference dots of known stellar brightness, allowing Astronomers to compare them to stars on photographic images in order to standardize measurements and identify changes in brightness.  The name comes from its resemblance to a fly-swatter, but it was considered too small to do a fly much damage.  A "blink comparator" was a device that allowed Astronomers to toggle rapidly between two photographic plates, in order to uncover differences visually.  Notably, use of this technique led to the discovery of the planet Pluto in 1930.