7.不同结构快门，闪光同步速度有区别，横走式布帘快门闪光同步速度一般在

A．1/8秒以下                                                           B.1/60秒以下

C.1/250秒以下                                                          D.1/1000秒以下

8.可以消弱或消除由非金属物体表面产生的反光的滤镜是

A．天光镜                                                                 B.柔光镜

C.阻光镜                                                                     D.偏振镜

9.在观察影像时，人眼感觉到的影像边缘密度变化的明锐程度称为

A.灰雾度                                                                    B.感光度

C.清晰度                                                                     D.宽容度

10.相纸的反差系数最小，称为软性相纸的是

A．1号相纸                                                              B.2号相纸

C.3号相纸                                                                 D.4号相纸

11.ＴＴＬ测光属于

A．入射式测光                                                         B.反射式测光

C.照度测光                                                                D.闪光式测光

12.拍摄潺潺的溪水，呈现出轻纱薄雾般柔美的影像效果。快门速度应是

A．10秒                                                                    B.1/60秒

C.1/250秒                                    &nbs