Digital Eclipse Time-Lapse Sequences

DDT Movies

Time-lapse sequences of recrystallizing DDT were captured with a Nikon DXM 1200 Digital Eclipse camera system attached to an E-600 microscope operating in polarized light mode.

DDT Video No. 1 - A spherulitic pattern was captured using polarized illumination at a magnification of 20x and a playing time of 12 seconds. Choose a playback format that matches your connection speed: 28.8k (modem), 56.6k (modem), or T1/Cable/DSL, or download this video clip in MPEG format (4.83 MB).

DDT Video No. 2 - Two large spherulite crystalline growth fronts collide under polarized illumination at a magnification of 40x with a playing time of 14 seconds. Choose a playback format that matches your connection speed: 28.8k (modem), 56.6k (modem), or T1/Cable/DSL, or download this video clip in MPEG format (5.7 MB).

DDT Video No. 3 - Multiple spherulites form and merge together in this digital time-lapse sequence. The crystal images were acquired with polarized illumination at a magnification of 10x and a playing time of 14 seconds. Choose a playback format that matches your connection speed: 28.8k (modem), 56.6k (modem), or T1/Cable/DSL, or download this video clip in MPEG format (5.73 MB).

DDT Video No. 4 - Observe several independent nucleation centers that ultimately fill the viewfield with spherulitic structures under polarized illumination at a magnification of 10x and a playing time of 12.5 seconds. Choose a playback format that matches your connection speed: 28.8k (modem), 56.6k (modem), or T1/Cable/DSL, or download this video clip in MPEG format (5.21 MB).

DDT Video No. 5 - Another set of nucleation centers that grow to full spherulites under polarized illumination at a magnification of 10x and a playing time of 11 seconds. Choose a playback format that matches your connection speed: 28.8k (modem), 56.6k (modem), or T1/Cable/DSL, or download this video clip in MPEG format (4.43 MB).

This organochlorine insecticide can be considered as the pesticide of the greatest historical significance, due to its effect on the environment, agriculture, and human health. First synthesized by a German graduate student in 1873, it was rediscovered by Dr. Paul Mueller, a Swiss entomologist, in 1939 while searching for a long-lasting insecticide for the clothes moth. DDT subsequently proved to be extremely effective against flies and mosquitoes, ultimately leading to the award of the Nobel Prize in medicine for Dr. Mueller in 1948.