Grossmann Michael, Schmidt Elmar, Haussmann Alexander
Arbeitskreis Meteore e.V., Kämpfelbach, Germany.
Appl Opt. 2011 Oct 1;50(28):F134-41. doi: 10.1364/AO.50.00F134.
The first likely photographic observation of the tertiary rainbow caused by sunlight in the open air is reported and analyzed. Whereas primary and secondary rainbows are rather common and easily seen phenomena in atmospheric optics, the tertiary rainbow appears in the sunward side of the sky and is thus largely masked by forward scattered light. Up to now, only a few visual reports and no reliable photographs of the tertiary rainbow are known. Evidence of a third-order rainbow has been obtained by using image processing techniques on a digital photograph that contains no obvious indication of such a rainbow. To rule out any misinterpretation of artifacts, we carefully calibrated the image in order to compare the observed bow's angular position and dispersion with those predicted by theory.
首次报道并分析了在露天环境中由太阳光引起的三级虹的可能的摄影观测结果。虽然主虹和次虹在大气光学中是相当常见且容易看到的现象，但三级虹出现在天空的向太阳一侧，因此很大程度上被前向散射光掩盖。到目前为止，已知只有少数关于三级虹的目视报告，没有可靠的照片。通过对一张没有明显三级虹迹象的数码照片使用图像处理技术，获得了三级虹的证据。为了排除对伪像的任何误解，我们仔细校准了图像，以便将观测到的虹的角位置和色散与理论预测的结果进行比较。
