高清现场录像机现场生产-更新!

更新:NAB 2013关于Atomos武士 Blade的新采访

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更新:来自NAB 2013关于声音设备Pix240i的新采访

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在本系列关于网络广播视频制作的早期文章中，我讨论了 视频切换器的角色 并提供了几种不同型号的概述在10000美元以下的市场. 在这篇文章中，我将讨论外部录像机, 具体来说是在录制主节目的作用下，从一个活开关中输入.

记录历史

I got my first external recorder in early 2005--the 40GB Firestore FS-4 that recorded DV via FireWire. I eventually upgraded the firmware with the HDV codec and replaced the hard drive with a 120GB model for longer record times. Then in 2008 I started using the Sony HVR-MRC1 CF recorder that came with my Sony HVR-Z7U. It accepts a FireWire input but also clipped directly on my old Sony video cameras (I bought a Sony Z5U as well) for a direct connection. I could use either of these models to record the program output from my 视频转换器 if I first converted the analog output to FireWire; for this, 我用的是Canopus Twinpact 100.

What I liked about these recorders is that they extended the record time from 60 minutes on tape to 2.在32GB的CF卡上5个小时，在40GB的FS-4上3个多小时. 比特率也是非常合理的25Mbps. 不幸的是, both were limited by FAT32 recording that broke the files into 4GB chunks that needed to be restitched with a special utility or they suffered from audio drop-outs and drift on longer recordings. I also fell out of love with the HDV codec when I switched to the full-raster AVCHD codec on my Sony FS100 and upgraded my video switcher to a digital HD switcher: the Blackmagic Design ATEM 1 M/E.

但就在我卖掉高清摄像机之前, I bought a pair of Atomos Ninja HDMI recorders in an attempt to improve their recording quality. It worked beautifully but there is only so much improvement you can realize before you run into another limitation: The signal-to-noise ratio on the 1/3” CMOS sensors was relatively low to begin with when you compare it to the low-noise image from a large-sensor video camera like the Super35mm Sony FS100 and FS700 that I now own. 一个嘈杂的图像是不可取的，特别是当网络广播，我做了很多. 我把两台摄像机都卖了, 一个忍者, 以及上面的所有内容, 除了twimpact 100, 我无法卸载——火线端口最终烧坏了, 作为sd专用设备, 它已经过时了.

我一直用忍者作为我的主录音机, but after too many frustrations with the HDMI format--mainly the HDMI EDID interconnecting that makes HDMI unstable, especially when split and over long distances--I moved all inputs and output to HD-SDI. 这就要求我们重新审视外部高清记录设备, 专门用于记录我的视频切换器的HD-SDI程序输出.

现代高清录像机

There are two form factors for external HD recorders: portable/camera-mount and rackmount. 一些公司生产两种规格的类似机型，如AJA Ki Pro (下面的图1)及Ki Pro Rack (图2，在图1下面).

图1. 便携式AJA Ki Pro

图2. 机架安装AJA Ki专业机架

就我的目的而言, 我并不一定需要把录音机装在架子上, 虽然在我的工作流程中，机架式单元更方便. 我更关心输入, 记录选项, 音视频监控, 电源选项, 恢复选项, 以及记录媒体.

视频输入和输出

我决定HD-SDI是我想要支持的原生格式. 如果我需要一个HDMI输入，我总是可以使用一个简单的HDMI到HD-SDI适配器, but the other way around puts me into HDMI EDID interconnect territory and that scares me.

On the video side, most of the HD-SDI devices that I looked at have an HD-SDI pass-through (下面的图3), which is nice when you want to connect a backup recorder (more on why you might want to do so later). 一些早期的HDMI录像机, 就像最初的原子忍者一样, 没有直通输出，但较新的忍者2有直通HDMI输出.

图3. 在Atomos武士号上的HD-SDI传输

一些录像机有视频屏幕来显示你的视频输入是稳定的. 一些便携式设备, 比如《百家乐软件app最新版下载》和《百家乐软件app最新版下载》, 注意力达到峰值, 可调节的斑马, 假彩色, and Blue-only features that add more confidence that the image is in focus and properly exposed (下面的图4).

图4. 关注《百家乐软件app最新版下载》

我觉得用没有屏幕的录像机不舒服, 但不幸的是，即使是一些更受欢迎的型号也是如此. 如果我用的是没有视频屏幕的外置高清录像机, I would pair it with an HD monitor so that I could see that the image is exactly what I expect it to be. In general, I would prefer to forgo the additional monitor but this isn’t so easy. 如果不是缺少视频屏幕，就需要这个额外的监视器, it’s the lack of two basic audio monitoring tools that will--more on this in a bit.