White Dots

• by Antarctica09

  What are these? Are they fireflies or similar or are they just some sort of lens artefact?

  Posted June 26, 2015 1:19 PM

• by davidbygott moderator

  These are raindrops. Note they all seem to be moving vertically. But why do they look as though they are flying upwards? Perhaps that is a flash artefact - e.g. the flash intensity starting very bright and dimming before it quits. Someone with more tech knowledge could probably explain better.

  Posted June 26, 2015 7:11 PM

• by tillydad moderator

  I believe that it is because the raindrops are falling at terminal velocity and the flash is capturing the position of it when it first operates and the "tail" appears as the raindrop continues falling at full speed within the duration of the flash itself. The full raindrop has not travelled sufficiently to appear as a sphere and we see the "tail" as the first part of the movement of the raindrop.

  I hope that this helps and that I have explained it clearly enough 😃

  Posted June 27, 2015 10:26 AM

• by aliburchard scientist, translator

  @tillydad that was a fantastic explanation...thanks 😃

  Posted July 8, 2015 10:59 PM