Please read the White Paper Copyright Notice

Download
WHP034 -
Addendum 8 1.27 Mb

WHP034 main listing

BBC R&D White Paper WHP034

Colorimetric and Resolution requirements of cameras

Addendum 8 (rev 7): Menu settings for Panasonic DVCProHD  AJ-HDC27F Varicam (720/4~60Hz proscan)
Alan Roberts

Abstract
Assessment was made on several AJ-HDC27F cameras at various times. It is a 720-line progressive variable frame-rate camera, and all menu items refer to this camera only. The camera is a refinement of the 27V which is also a development of the 27. The 27H differs only trivially from the 27F, all the settings in this document will work equally well in either camera; however, setup cards recorded in the F will not work in the H, or vice versa, although there is a Panasonic utility to convert between the formats if necessary.

The camera has 3 ccds, each of 1280x720 pixels. The tape speed is constant despite any camera frame rate changes, the tape always runs at 60 (or 59.94) frames/second. When the camera is set to run at lower frame rates, replicated frames are recorded as needed to fill the tape. Thus, the pictures can be monitored using a fixed frame-rate display. A special hardware/software system is required to extract frames from the tape to reconstruct a sequence of non-replicated frames at 24 per second. Nominal frame rate is 24fps, so the camera can effectively record between 2.5 times (60fps) and 1/6 (4fps) normal speed. If the camera is set to 24fps, then the tape is effectively performing a "3:2 pull-down" operation as is normal for film work in 59.94Hz countries.

The camera is smaller and lighter than the familiar Beta camcorder and is useful mostly for portable, single-camera work. It has very many internal menus for setting the performance, and two versions of most of them, giving a range of combinations that it has been impossible to investigate thoroughly in the limited time available. There are three distinctly different modes in which it can operate. It is clearly designed with the intention of supplanting film, both for television and for printing back to film for distribution.

Panasonic have a DVD that shows how some of the more important features work, and how menu values can be used to manipulate pictures. Potential users of this camera are very strongly advised to get this DVD and study it at length in order to exploit the best features of the camera, it’s ability to mimic film negative performance and variable speed recording. Even the DVD is not sufficient for the user to get the best from the camera, the combination of DVD and manual will explain how it all works, but laboratory work is needed to ensure the best performance in any mode. The settings given here are neither exclusive nor exhaustive, the user is strongly advised to seek specialist help before shooting.

This revised version has some more modifications resulting from field experience in varied conditions; it also incorporates settings designed specifically for Natural History productions, and recommendations for use in keying.

Keywords
camera, colorimetry, gamma, knee, aperture correction, detail enhancement, film look, shuttering