Zeiss Super Speed Lens Coverage of the GH2 and BlackMagic Cinema Camera
by danielgrey
I regularly use a set of Zeiss Super Speeds (MKii) that are designed for the Super 16mm format. I love using them when filming just because they are just so damn easy to use. Designed for use on a film set they have an industry standard focus gear built in and the aperture and focus rings are oil dampened. There is also a look to the images captured by the Zeiss that sets them apart from other lenses. Some people mention the look may be due to the demanding resolution requirements of the Super16 format and the lenses ability to render microcontrast.
The Zeiss come in a set including a 9.5mm, 12mm, 16mm, 25mm and a 50mm. They are all the same aperture, the same length and have the same front diameter allowing for speedy use on a rig with a matte box. The 25mm and the 50mm will cover a Super35 sized sensor (roughly the same size as an APS-C digital sensor), the others will not. I use the Zeiss lenses on a Panasonic GH2; it has a feature that uses a smaller crop of the sensor allowing me to use the full set of lenses.
These lenses should cover the 12.85mm x 9.64mm sensor of the upcoming Digital Bolex but I’m also interested in the upcoming BlackMagic Cinema Camera (the BMCC). I couldn’t find definitive info on the image circle of the Zeiss Super Speeds so I thought I would do a rough test. I know the sensor of my GH2 in 4:3 aspect ratio is 17.3mm x 13mm so I took some photos of the image circle of the lenses. Popped the images into my computer and measured the revealed circle in photoshop. This is not a millimeter perfect test of the image circle but I think it’s pretty close.
All the lenses were set to f16 and infinity giving the smallest image circle. Basically this is a worst case scenario of what these lenses will cover. The black box in the image below that represents the BlackMagic Cinema Camera sensor. The Zeiss 16mm will cover the 18.09mm diagonal of the BMCC and the 12mm comes close to working. In fact I assume when the aperture is wide open the 12mm will cover with slight vignette. The 9.5mm would really struggle unless BlackMagic introduces a crop feature of the sensor which is quite possible in their 1080P ProRes or DNxHD modes.
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As for the lens set coverage of the whole sensor on the GH2 it’s multi aspect sensor means that although the 16mm lens is visible on the frame in 4×3 it’s minimized to a small vignette on the 16×9 aspect ratio of the video mode.
”Th-Th-Th-Th-Th-… That’s all, folks”
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Hi Daniel. Nice work. Are you using these lenses on ETC mode on the gh2, and not with the the full sensor. We are having a discussion about your findings on the BMCC forum here:
http://bmcuser.com/showthread.php?2228-Zeiss-Super-Speed-Lens-Coverage-of-the-GH2-and-BlackMagic-Cinema-Camera&p=41299#post41299
As you can see in the image above the 9.5mm, 12mm and 16mm vignette on the full sensor of the GH2. So I use the ETC mode if I want to use these lenses without a vignette. The 25mm and 50mm don’t vignette so I can use them on the GH2 without the ETC mode.