Wide-field image of the DNA sample.
(a) Unter atomic filtering (T = 200°C). The acquisition time per frame is 10 s. (b) Same with filtering by the commercial filter. (c) Line-cut of a single molecule (yellow dashed line). The wide-field configuration is more sensitive to scintillations that causes temporal changes in the refractive index of the air. As a consequence the image is blurred out.