谈起心爱的CP.2，专业测评人Nigel Cooper也疯狂

#设备体验# 卡尔蔡司定焦镜头CP.2

蔡司镜头CP.2 - 很可能是数字电影领域最好的镜头！

如果你是一个资深的数字电影制作人，卡尔蔡司CP.2镜头应该是你考虑的镜头列表中数一数二的。

蔡司CP.2系列是蔡司最新的专为数字和胶片摄像机设计的系列镜头。2011年2月，增加了可交换镜头卡口种类，让镜头有一个更广泛的运用，从电影胶片摄像机到数字电影摄像机甚至数码单反相机。以松下AF103，索尼F3和佳能的EOS为例。这种镜头卡口系统是不像老腾龙Adaptall镜头系统一样含糊，quick-release型。相反，蔡司是更专业和强大的系统，semi-permanent型。作为一个松下AF103摄像机的用户，只需要蔡司CP.2的（MTF）卡口镜头，也不需要第三方转接环。该CP.2镜头不仅有MFT卡口，还有阿莱PL，佳能EF和尼康卡口。蔡司CP.2镜头应该是唯一涵盖诸如佳能EOS 5DMK2这样的全画幅24x36mm传感器照相机的电影镜头了。

他说他已经是松下的AF103的粉丝了，所以他选择了103来测试这些镜头。AF103是MTF卡口（M4/3）。 在他看来，AF103是数字solid-state版本的35mm电影摄像机，但是要在使用正确配件的情况下。像是记录器如AJA Ki Pro Mini, 遮光罩，跟焦器如Chrosziel，还有镜头当然至关重要。有了这些附加组件AF103将变成准数字电影制作工具了。

一个简单的历史。阿莱“PL”接口镜头源于“Positive Lock”。它是发展于阿莱80年代末的16毫米和35毫米电影摄影机使用的卡口，阿莱可更换镜头卡口。

CP.2什么意思？简单、紧凑的定焦。数字2只是蔡司区别于第一代。

28mm，50mm和85mm，它们的最大光圈都是F2.1最小光圈F22。其实，这些镜头都是T光圈，而不是为F光圈。所有这三个镜头是相同的尺寸，即使他们使用了遮光罩还是调节了光圈环。

光圈T值

关于T值和F值区别的解释。

T值透光率是根据像平面的照度测得的。所以，光圈值T是测出来的。因为T值考虑了各种因素对镜头的透光率的影响，因此，只要两个镜头的T值一样，其光通量一定是一样的。F值镜头入射光孔直径取决于光阑直径，光阑是用来限制成像光束的大小和形状的装置。可见，光圈值F是计算出来的。并且，光圈值F没有考虑镜头的光学结构，镜片的材料，镜片的镀膜等对镜头透光率的影响。所以，T值比F值更科学，更精确。

不过，由于镜头镀膜技术的发展，T值与F值的差异已经很小了。对一般摄影来说，F值已经可以满足需要。T值多用在对曝光要求更严格的电影摄影镜头上。

（抱歉，这段不是原文翻译，与其翻译不准确还不如另找的关于T值与F值的解释）

视野

值得一提的是松下AF103在上了CP.2镜头后会有视野会有一些变化。这是因为蔡司CP.2是全画幅镜头。很早以前，这些镜头是摄影镜头;蔡司做了非常多大量的工作去把这些摄影镜头变成专业电影镜头。电影胶片摄像机的传感器，比上松下AF103传感器大了大约23.6％。电影胶片是22mm宽，AF101传感器17.8mm宽。这（按外行人的话说）是指一个蔡司CP.2 50mm镜头安装在松下AF103将有相当于实地的视图60mm（61.8是精确的），所以轻微的放大了。

CP.2镜头的视图与松下AF103对照表：

CP.2 28mm在AF103上相当于35mm（34.608精确）在电影摄影机上

CP.2 50mm在AF103上相当于60mm（61.8准确）在电影摄影机上

CP.2 85mm在AF103上相当于85mm至105mm（105.06精确）在电影摄影机上

如果你把CP.2装在佳能EOS 5D MK2（全画幅）上，其视图将保持50mm。

打造精品

当你把蔡司CP.2拿到手中，你会马上感觉出这一个非常高品质的镜头。够分量（相比，松下Lumix自动对焦镜头）具有坚实的金属结构。徕卡曾有一句话，如果你买了徕卡相机，并不代表你会拥有它，你仅仅是在你在世时占有它而已。他认为，这话同样适用于这些蔡司CP.2镜头。在机械方面则沿袭了高精度手工制造手瑞士表和1980年的哈苏相机的水准。光圈环结合紧密却又难以置信的顺滑，显然是专为电影拍摄设计的。内部光圈由14个高精度叶片组成，保持足够圆和对称。对图像质量而言，这意味着什么呢？它将会呈现一个自然平滑的背景虚化。聚焦精确。至于光学器件，蔡司十分讲究。镜片的成色、匹配是手工挑选。该镜头还有小挡板在后面，以帮助控制镜头眩光。德国制造。

操作

蔡司打电话给他，问他是否需要在镜头上用英尺或米标记（没错，他们正在为他加工了）。他使用英尺就像一般跟焦员喜欢用英尺工作一样。这种镜头是跟焦员的梦想，这样跟焦员就可以站在摄像机的任何一边工作。

由于对这些镜头（有更严格和准确的齿轮聚焦）当使用Chrosziel跟焦器和一个附加手柄时，一切将变得更加容易了。Chrosziel也是德国品牌，它们是天生一对。

镜头是否有可移动的部分（凭着两个六角螺丝）?英寸标准螺纹口你可以添加保护镜头的遮光罩什么的。即使CP.2镜头比较重（约1公斤），相比尼康摄影镜头，还更适合安在AF103，非常稳。

114mm的镜头直径，使用遮光罩也不影响。这些镜头调焦都在内部完成，因此镜头的长度不会变化。

图像质量

这是很重要的部分。他已经使用CP.2在AF103上拍摄好几个月了，并在Final Cut Pro上编辑了，所以他有一些对镜头的特性和图像质量的看法。

一个很牛的事情是这些镜头是不会有呼吸效应，不像相机镜头。即便是一些是一些ENG系统镜头仍然会有focus breathing现象。这些CP.2镜头没有任何可怕focus breathing现象。他们也几乎无任何颜色畸变和散色或是带色边。这些CP.2其极端的精密确保低失真，分辨率高，色彩还原非常出色，锐利的极具冲击力的图像。

总的来说，CP.2最后生产的图像非常的自然，颜色是令人难以置信地具有冲击力，同时又保留了自然的审美感。对比度也简直完美的，分明却又光滑;与电影的完美结合。这些镜头让他想起早在20世纪80年代的卡尔蔡司镜头和哈苏500CMs相机，也相当的锐利。但如今在CP.2与现代数字摄像机上也能实现类似的质量和清晰度。

他觉得自己这些对镜头构造和图像质量的描述都是轻描淡写了。他非常喜欢使用这些镜头，也大爱这些镜头出的图像。“他们是梦一般光滑精确的对焦和光圈控制，后期当你编辑那些素材时也像在作梦似的。”

价格

CP.2镜头大约要2,760英镑（不包括税，约29339人民币），这已经远远低于传统的35毫米电影电影镜头，这是相当多的平均成本。如果你买一套的话价格还会更便宜。他们会数字电影制作中最好的镜头。

CP.2系列

总共有七个CP.2镜头，它们如下：18mm T3.6，21mm T2.9，25mm T2.9 ，28mm T2.1，35mm T2.1 ，50mm T2.1和85毫米85mm T2.1。

英文原文：

Carl Zeiss Compact Prime CP.2 Lenses

Zeiss CP.2 lenses – probably the best lenses in the world for digital video filmmaking!

If you are a serious digital video filmmaker, the new Carl Zeiss CP.2 (Compact Prime) lenses should be at the top of your list of lenses to look at; or at least very near to the top of it.

Zeiss’s CP.2 range of primes are the very latest members of the Zeiss family of lenses designed specifically for both digital and film cameras. And as of February 2011 they are now available with interchangeable mounts that allow the lenses to be used with a wider range of cameras from traditional cine film cameras to modern digital camcorders and DSLRs such as the Panasonic AF101, Sony’s F3 and Canon’s EOS 7D and 5D MK2 for example. This interchangeable mount system is not one of the quick-release type like that of the old Tamron Adaptall photographic lens system from years ago, which could feel a bit vague. Instead, Zeiss use a professional and robust system that is semi-permanent. The mounts are attached via four allen key type countersunk screws so it is to be assumed that if you want a PL mount, you would buy it this way and stick with that PL mount as there is nothing fast about changing the mounts over in the field. As an owner/user of the Panasonic AF101 film-like HD camcorder, I asked Zeiss in Germany to send me over three CP.2 lenses with the Micro 4/3rd (MTF) mounts on them. These fit directly onto the Panasonic AF101 with no need for a third party mount. The CP.2 lenses are available not only in MFT, but also Arri PL, Canon EF and Nikon. From what I can gather, these CP.2 lenses are the only cinema style lenses that will also cover a photographic full-frame sensor of 24x36mm such as that of the Canon EOS 5D MK2.

I\\\\\\\\\\\\\\\'ve become something of a fan of Panasonic\\\\\\\\\\\\\\\'s AF101 film-like HD camcorder, so it seemed obvious to test these lenses with this camera. The AF101 has a MTF (micro four third) mount and the Zeiss lenses are now available as an MFT mount option.

The way I see it, the Panasonic AF101 is a digital solid-state version of a traditional 35mm cine film camera, but with the right accessories, such as a decent digital recorder on the back such as the AJA Ki Pro Mini, a nice matte box and follow focus unit such as those from Chrosziel, and of course decent glass on the front. With these add-ons the AF101 becomes a serious digital filmmaking acquisition tool.

A brief history lesson. The “PL” in Arri PL mount lenses stands for “Positive Lock”. It was developed by Arri in the late 1980’s for use with both 16mm and 35mm movie cameras and is a replacement for Arri bayonet mount.

What does CP.2 stand for? Simple. Compact Prime. The number 2 is simply Zeiss’s way of distinguishing these new lenses from the first generation Compact Primes. They are named such because they are compact when compared to other modern cine lenses such as Zeiss’s own Master Primes or some of the Cooke range for example.

The three lenses I’m reviewing here are the 28mm, 50mm and 85mm, all of which are F2.1 at the fastest end, going down to F22. Actually, these lenses are set in T-stops, as opposed to F-stops; see below for explanation. All three lenses are identical in dimensions so swapping them over during a production doesn’t require you to swap matte box doughnut rings or move rails back and forth etc.

T-STOPS

A little about T-stops. If you have never heard of T-stops before, here is an explanation of what the difference is between T-stops and F-stops.

Since all lenses absorb some portion of the light passing through them (particularly zoom lenses containing many elements), T-stops are sometimes used instead of F-stops for exposure purposes, especially for motion picture camera lenses. The T in T-stop stands for transmission. The practice became popular in cinematographic usage before the advent of zoom lenses, where fixed focal length lenses were calibrated to T-stops. This allowed the turret-mounted lenses to be changed without affecting the overall scene brightness. Lenses were bench-tested individually for actual light transmission and assigned T stops accordingly. Modern cinematographic lenses now usually tend to be factory-calibrated in T-stops. T-stops measure the amount of light transmitted through the lens in practice, and are equivalent in light transmission to the F-stop of an ideal lens with 100% transmission. Since all lenses absorb some quantity of light, the T-number of any given aperture on a lens will always be greater than the F-number. In recent years, advances in lens technology and film exposure latitude have reduced the importance of T-stop values. So, F-stops are for focal ratio, T-stops are for transmission.

FIELD-OF-VIEW

It’s worth noting that on the Panasonic AF101 the field-of-view with these lenses changes a little. This is because the Zeiss CP.2 lenses are full frame lenses. Way back, these lenses were photographic stills lenses; Zeiss have done a great job of taking them from a top shelf photographic stills lens to a set of professional motion picture primes. The sensor size (or film gate opening) on motion picture film cameras is about 23.6% larger than the sensor on the Panasonic AF101. Motion picture film is 22mm wide and the AF101 sensor is 17.8mm wide. This (in laymen’s terms) means that a Zeiss CP.2 50mm lens mounted on the Panasonic AF101 will have the equivalent field-of-view to that of a 60mm (61.8 to be exact), so a slight magnification.

CP.2 Lens field-of-view chart for Panasonic AF101:

CP.2 28mm on AF101 equates to 35mm (34.608 exactly) on a motion picture camera

CP.2 50mm on AF101 equates to 60mm (61.8 exactly) on a motion picture camera

CP.2 85mm on AF101 equates to 105mm (105.06 exactly) on a motion picture camera

If you put a CP.2 50mm on a Canon EOS 5D MK2 (full frame), its field-of-view will remain 50mm.

BUILD QUALITY

When you first take a Zeiss CP.2 lens out of its box and hold it in your hand, you will immediately know that you have purchased a very high quality precision lens. They are heavy (when compared to say a Panasonic Lumix AF lens) with a solid metal construction. You get the impression that these lenses will last a lifetime and beyond. A Leica rep once told me that if you buy a Leica camera, you don’t own it, you merely possess it while you are on the earth. I think that same saying can be applied to these Zeiss CP.2 lenses. The mechanical side to them is along the lines of a precision hand-made Swiss watch or a 1980’s Hasselblad camera. The aperture ring is just taut enough and incredibly smooth, and obviously because they are designed for motion film and video, it is click-stop free. The internal aperture mechanism consists of 14 high-precision blades that remain constantly round and symmetrical over the entire F-stop range. What does this mean in terms of image quality? It results in very natural and pleasing out-of-focus highlights with a very smooth bokeh. The focusing barrel continues in the same precise manner. It is nice and taut and incredibly smooth. As for the actual optics, Zeiss are fastidious in this department. The glass is colour matched and hand-picked. The lenses also have a small baffle over the rear element to help control lens flare. Everything about these lenses smacks of high quality and precision; they are made in Germany.

OPERATION

Zeiss phoned me to ask if I wanted the markings on the focus barrel to be in feet or metres (that’s right, they made them for me on the factory floor). I specified feet as in the UK focus pullers generally prefer to work in feet. These lenses are a dream for focus pullers; for example, there are distance markings on both the right and left side of the lens so focus pullers can be standing either side of the camera while working. The same goes for the aperture ring markings.

Because of the longer focus rotation on these lenses (allowing more precise and accurate rack focusing), pulling focus will be made easier with a Chrosziel Follow Focus unit with an additional crank handle. The CP.2 lenses aperture ring and focus barrel are geared to accommodate follow focus units. I mention the Chrosziel brand here simply because they too are made in Germany to the same very high engineering standards as the Zeiss CP.2 lenses; they are a match made in heaven.

The lenses come with a removable (by means of two allen key screws) ? inch standard tripod style screw thread so you can secure the lens even more to a matte box rail system. I found that even though the CP.2 lenses are relatively heavy (about 1 kg) compared to say a Nikon stills photographic lens, they fit securely onto the Panasonic AF101 very securely with zero give in the mount of the camera. They are going nowhere, so there is no real need to secure them further.

The 114mm front diameter is nice as it means when you are using a matte box, there is no need to keep swapping out doughnut rings. The focusing of these lenses is internal so the length of the lens remains the same during focusing which means matte box setups are not compromised.

IMAGE QUALITY

Now for the all-important part. I’ve now been shooting with these three CP.2 primes on the Panasonic AF101 for a few months now and have been editing the footage in Final Cut Pro so I now have a good idea of the lens characteristics and image quality.

The first great thing about these lenses is that there is no focus breathing, unlike photographic stills lenses, which are not designed for video. Even some ENG style video lenses suffer from focus breathing. These CP.2 lenses are free of any horrible focus breathing phenomenon so your pull-focus shots will look amazing. They are also pretty much free of any colour aberrations and vignetting around the edges of the image. These modern CP.2 prime lenses with their ultra tight tolerances ensure low distortion, high resolution and superb colour rendition resulting in very sharp and punchy images.

Overall I found the image quality produced by the CP.2 lenses to be incredibly natural. The colours are incredibly punchy, while retaining a very natural look. Contrast is just perfect, crisp, yet smooth; a perfect combination for serious filmmaking. These lenses really are tack-sharp, they remind me of my stills photographic days of using Hasselblad 500CMs with Carl Zeiss lenses; back in the 1980’s they were tack-sharp also. But now we have that same build quality and sharpness in the all-new Zeiss CP.2 lenses designed specifically for modern digital video applications.

To say I’m blown away by both the build and image quality of these lenses is an understatement. I totally love using these lenses and I’m in love with the images they produce. They are a dream to use with smooth precise focusing and aperture control and that beautiful dream continues in post-production when you are editing the footage.

PRICE

Although these CP.2 lenses cost approximately ￡2,760 each excluding vat, this is well below the average cost of traditional 35mm motion picture cinema lenses, which are considerably more. If you buy a set of Zeiss CP.2 lenses the price works out cheaper. What you are getting with these Zeiss CP.2 lenses is about as good as you can buy. I don’t know if I would go as far as saying that they are the best lenses you can buy for cine camera moviemaking, but they are definitely right up there. However, I certainly feel that they are probably the best you can buy for digital video filmmaking.

CP.2 RANGE

There are seven CP.2 lenses in total, they include the following: 18mm T3.6, 21mm T2.9, 25mm T2.9, 28mm T2.1, 35mm T2.1, 50mm T2.1 and an 85mm T2.1.

For more technical details visit: www.zeiss.com/cine

来源：dvuser，更多技术细节，请访问：www.zeiss.com/cine