[Tig] HDCAM for 2.35 (again!)

Rick_Harding at spe.sony.com Rick_Harding
Fri Nov 2 03:51:54 GMT 2001

> This seems to be Sony's take for now with their Cinealta line
including the
> Vialta telecine that scans at "only" 1920 x 1080?  Re-scanning for
> maybe more economical then an original 2K or 4K scan of everything ?

Yes, Vialta scans 1920 x 1080.  This is scanned at full bandwidth RGB
(22:22:22) using fixed arrays.  444 RGB imaging, outputted in real time
10 bit log (or 10 bit linear), yields benefits back to film that exceed
422 sampled images in 2K format.  Increased exposure time allowed by
intermittent capture contributes significantly to the process. All lines
of video are exposed at the same time allowing for milli-second exposure
periods compared to the micro-second exposure time of continuous motion

Optical zoom capability in the telecine allows framing for 1.85 and 1.78
without the need for digital zoom.  So if you are working with Super 35
and framing for 1.85 or 1.78, you can accomplish the desired sizing
without suffering digital interpolation.

As for 2.35 aspect ratios, Vialta is equipped with an anamorphic
conversion lens that maps the full aperture image to the full array.  In
this case you would size top and bottom, and the anamorphic lens will
de-anamorphisize (made that word up myself..) the film image to fit the
array side to side. This ensures that you have full 1080 vertical
sampling while sampling the entire film frame 1920 horizontal.
Achieving 2.35 from there does require further de-anamorphisis, but this
is accomplished electronically as is any pan and scan, or subsequent
zoom move.  The same is true when sampling the entire aperture of 1.33
or Super 35.  Another lens squeezes the film image top and bottom while
sizing side to side, sampling the whole frame.

Not a sales pitch, just a few facts that may clear up some
mis-conceptions about how Vialta works.

Rick Harding

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