camera简单

A butterfly takes off so quickly it is still impossible to react quickly enough to capture that take-off but if he half-presses the shutter, the camera saves the 70 previous frames before the moment he actually takes the picture.

蝴蝶起飞得太快，人仍然不可能反应快到捕捉到起飞的那一刻，但如果他半按快门，相机就会保存他真正按下快门之前的70帧画面。

Peters’ signature shot is a butterfly “take-off”, showing the multiple wing-beats of one butterfly in one frame as it lifts off from a flower. How does he capture it? Technology helps. A typical digital SLR camera shoots 20 frames a second. He uses a high-speed OM System which shoots 120 frames a second.

彼得斯的招牌镜头是蝴蝶“起飞”，在一帧画面中展现一只蝴蝶从花朵上起飞时的多次振翅。他是如何拍到的？技术帮了忙。一台普通的数码单反相机每秒拍摄20帧，而他使用的是每秒可拍120帧的高速OM System相机。

Throughout the trip, Jackson juggled multiple cameras and plate sizes using the “collodion process” that required him to coat the plates with a chemical mixture, then expose them and develop the resulting images with a portable darkroom. The crude technique required educated guesses on exposure times, and involved heavy, awkward equipment — several men had to assist in its transportation. Despite these challenges, Jackson captured dozens of striking photos, ranging from majestic images like his now-famous snapshot of Old Faithful, to casual portraits of expedition members at the camp. While veterans of previous expeditions wrote at length about stunning trail sights, these vivid photographs were another thing entirely.

在整个旅途中，杰克逊使用“火棉胶工艺”同时摆弄多台相机和多种尺寸的底片，这种工艺要求他先给底片涂上一层化学混合物，然后曝光，再用便携式暗室冲洗出影像。这种简陋的技术需要凭经验推测曝光时间，而且所用设备笨重难使——需要好几个人协助搬运。尽管困难重重，杰克逊还是拍下了几十张引人注目的照片，从他那张如今已闻名于世的老忠实泉快照这样的壮丽画面，到营地里考察队员的随意肖像，不一而足。以往考察的老手们曾长篇累牍地描写沿途的壮丽景色，而这些生动的照片则完全是另一回事。

The thought of holding a fixed grin as the camera performed its magical duties was too much to contemplate, and so a non-committal blank stare became the norm.

在相机施展魔法期间一直保持咧嘴笑的表情，这简直不堪设想，因此不置可否的茫然凝视就成了常态。

But exposure times were much quicker by the 1880s, and the introduction of the Box Brownie and other portable cameras meant that, though slow by today’s digital standards, the exposure was almost instantaneous.

但到了19世纪80年代，曝光时间已经快多了，而布朗尼盒式相机和其他便携式相机的问世意味着，尽管按今天的数码标准来看仍然很慢，但曝光几乎是瞬间完成的。

Their tension before the camera.

他们在镜头前的紧张。