什么是i法师?

图像放大 is I法师 玛格nification.

只要有人上台, 旁边有一个屏幕, 或其他地方, with a video camera providing an i法师 of that very same person, 这叫做图像放大. 目的是 玛格nify the person's "I法师" so people further from the stage can more easily see them. The usage of 图像放大 is very common in corporate events, 酒店和会议行业, 以信仰为基础的生产, 等.

绿亩浸信会教堂的信仰图像

图像是非常重要的. There is a strong relationship between the viewer and the presenter when the viewer can easily and comfortably see the person speaking. 它更强大. Face-to-face meetings work better than tele会议s. And even theatrical stage performers know not to deliver their lines while facing the back of the stage. People in the audience often feel as though they can't hear you if they can't see your mouth move. So it's a common theatrical "cheat" to walk backwards or diagonally while speaking. 被人看到是很重要的.

什么是意象，什么不是意象

In many cases, the i法师 on the screen is not always the zoomed-in shot of the speaker. This is because this same feed is also what is streamed out to users on the web, 或者作为事件的文档归档, 所以需要广角镜头, 观众镜头, 产品特写, 预先录制的视频片段, 幻灯片, 图形, 还有更多.

A PowerPoint or other computer-based 幻灯片how presentation on a big screen by itself is not typically called 图像放大. 也不只是视频播放. But when you mix in a camera that will shoot the person on stage, 这一切都变成了图像, and the video playback and slide presentation are generally expected to accompany it.

有两个关键因素使它成为“图像”:

• 长镜头相机
• 大投影屏幕

图像相机和镜头

提供图像放大的“放大”部分, you typically need a broadcast camera in the middle of the auditorium, 上面有一个大/长镜头. This lens is generally not designed to shoot subjects that are closer than 20 feet. It's designed to bring very distant things very close. Think of the big-box lenses that can show you the quarterback's face from the other end of the stadium. 通常是80倍, 100x and larger lenses and are operated on tripod setups that are designed to hold the massive lens up, 然后装上相机.

Canon DigiSuper72 lens (© 2011 CVM PRODUCTIONS, INC.)

So, technically, seeing the quarterback's face on the 200' in-stadium LED wall is 图像放大.

If you have a smaller camcorder with just a 20x lens that starts at a reasonable wideness, you'll need to do one (or more) of the following things to get the long zoom you need for proper 图像放大 in a sizeable venue:

• 在镜头前面加一个光学倍频器
• 如果可能的话，更换一个更长的镜头
• 把相机移近拍摄对象

An optical doubler is a large piece of glass that acts as 2x "binoculars" to double the zoom of your existing lens. You secure it in front of your existing lens to bring those distant subject closer and make them appear bigger. If you're going to do this often, buying one makes sense. 你也可以租. Below, a Century Converter optical doubler from Schneider Optics.

施耐德光学世纪转换器 optical doubler for the Panasonic HVX200

在可移动镜头相机上, there are often a variety of lenses out there that can be used instead of the stock lens that comes with the camera. 经常, 这些镜头可以从出租屋买到, 比如Bexel和其他人, 这将在全国范围内发货, 甚至在国际上. You can use the lens for your event, and then send it back.

佳能33x11镜头©MK Video Inc ..

最后, you can set up a camera platform in the middle of the room, or even cheat it closer to the stage and put it lower to the floor so you don't block the view for too many people. 这种方式, you can fill the frame with the face of the person who is speaking, 当图像被放到20英寸的屏幕上, the people all the way in the back of the room can clearly see the speaker speaking.

使相机更接近拍摄对象. 图片来源©模拟的方法