White Paper 034 Addendum 34 (rev 1): Assessment and settings for Sony HVR-Z5E and HVR-Z7E

Alan Roberts

Abstract

Data for this addendum is taken from a short examination of production model of each of the Sony Z5 (serial number 00001, clearly an early model) and Z7 HDV (a retailed model) camcorders and from their manuals. The cameras are nearly identical, therefore it makes sense to report on them together.

They are HDTV camcorders, physically very similar to the Z1, with 3⅓" cmos sensors, but the Z7 has an interchangeable lens with a Sony proprietary lens mount while the Z5 has an integral Sony lens. The manuals claim that the sensors are approximately 1.12 Megapixels, delivering resolution up to1440x810, with approximately 1,037 Megapixels used for 16:9 capture. They both record HDTV using the HDV algorithm onto standard DV tapes (1080i and 1080psf) or Compact Flash solid-state cards, and SDTV using DVCAM or DV format. The similarity to the Z1 is only superficial.

The cameras are relatively light (about 2.8kg in including lens and battery) and have an integral viewfinder, with side lcd panel, and seem aimed at the high-end professional market rather than full broadcast, which would normally demand an image format larger than ⅓". The lens mount of the Z7 is specific to the ⅓" format, but adaptors are available to permit the use of ½" lenses. The Z7 was tested using the supplied Zeiss 12:1 zoom lens.

There are internal menus for setting the performance, not as complex as in a full broadcast camera, but enough to control some of the important features, albeit only in “on/off” states. They are not well suited to multi-camera operation since they cannot be remotely controlled. There are analogue-only video outputs (components and SD-composite via a multi-pin connector and S-video SD) and digits via IEEE1394 Firewire (known as i.Link by Sony) and 8-bit HDMI. A broadcast camera would normally be expected to have a 10- bit HDSDI output.

The same assessment procedure was used as for other HD cameras, partly attempting to get a good “filmlook”, and the settings reflect that. However, because of the lack of internal test signals, it was necessary to make more complex measurements than normal, through the lens. Since many camera parameters are undefined in the specifications, more measurements than usual were necessary. In the search for a “filmlook” setting it is normal to think of the camera to be mimicking a film camera and telecine, with “best light” transfer to tape, with about 10 stops of tonal range. Assuming that a grading operation will be used in postproduction, the settings attempt to give the colourist the same range of options as with film, but without achieving the full 10-stop dynamic range. The recommended settings allow about 1.7 stops of over-exposure and one of under-exposure relative to normal operation. This is not as good as can be achieved in ⅔" cameras, and arises from the difference in pixel size (the pixels here are much smaller, so sensitivity is maintained at the expense of highlight handling and video noise).

Download White Paper 034 Addendum 34 (rev 1): Assessment and settings for Sony HVR-Z5E and HVR-Z7E

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