据说,早期的摄影术由于受摄影器材和感光材料的限制,大白天拍摄需要进行30分钟以上的长时间曝光。又没有大功率、性能稳定的灯具,所以拍人像时,被摄者要在晴朗的日子里被夹或被捆在结实的椅子上。并且不许眨眼,更不能动。倘若赶上天公不作美,那就只好另行约定了。看来那时的摄影师也是靠天吃饭。只是不知如果开拍后15分钟,天气发生变 It is said that early photography due to the photographic equipment and photographic materials, daytime shooting requires more than 30 minutes long exposure. There is no high-power, stable performance lamps, so when portraits, the photographer to be caught in a sunny day or be tied in a solid chair. And not allowed to blink, but can not move. If you catch up with God is not beautiful, then had agreed otherwise. It seems that photographers are also dependent on the weather to eat. Just do not know if 15 minutes after shooting, the weather changed