Save time with this exposure calculator for Iridium-192, Selinium-75 and Cobalt-60 sources. No more need to calculate the formula or use of the "old-school plastic calculator" Simply fill in the thickness, activity(in Curies) and source-film-distance and you get the correct exposure time. R factor for different densities and film types. 节省时间与本次曝光计算器，铱-192，Selinium-75和钴60的来源。 没有更多的需要计算出“老派的塑料计算器”的公式或使用 只需填写厚度，活动（在居里夫妇）和源胶片的距离，你会得到正确的曝光时间。 R因子的不同密度和电影类型。 更新内容： + Introduction of GammaCalc Pro (26-03-2015)