Carl Zeiss Compact Prime CP.2 Lenses
Zeiss CP.2 lenses Ė 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.
Zeissís 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, Sonyís F3 and Canonís 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 ďPLĒ in Arri PL mount lenses stands for ďPositive LockĒ. It was developed by Arri in the late 1980ís 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 Zeissís 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 Zeissís own Master Primes or some of the Cooke range for example.
The three lenses Iím 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 doesnít require you to swap matte box doughnut rings or move rails back and forth etc.
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.
Itís 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 laymenís 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.
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 donít 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 1980ís 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.
Zeiss phoned me to ask if I wanted the markings on the focus barrel to be in feet or metres (thatís 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) ľ 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.
Now for the all-important part. Iíve 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 1980ís 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 Iím blown away by both the build and image quality of these lenses is an understatement. I totally love using these lenses and Iím 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.
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 donít 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.
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
To buy securely online visit one of these official UK importers:
©2011 Nigel Cooper
Reviewed by: Nigel Cooper
Review Date: 01-06-2011