Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!uxc!deimos.cis.ksu.edu!rutgers!att!mtuxo!lzfme!jwi
From: jwi@lzfme.att.com (Jim Winer @ AT&T, Middletown, NJ)
Newsgroups: comp.graphics
Subject: Re: Expanding your camera's dynamic range
Summary: Internal adjustment on professional cameras
Message-ID: <1326@lzfme.att.com>
Date: 9 May 89 17:11:24 GMT
References: <3113@tank.uchicago.edu>
Organization: AT&T, Lincroft NJ
Lines: 29

In article <3113@tank.uchicago.edu>, james@rover.bsd.uchicago.edu writes:
> 
> 	I have a problem, in that I am digitizing x-ray films with ...
> a ccd camera. ... Many problems of local
> contrast enhancement and noise can be addressed by image processing methods,
> but the overall contrast range is limited by my camera and digitizer (8 bits).
> 
> James Balter

On industrial ($1,500 up) and broadcast cameras ($15,000 up) there is
an internal adjustment that is used to set the signal level. You can
adjust the black level (knee at 7.5 IRE units?) and the maximum
white level. Thus, you can set the dynamic range to match your needs
exactly. You will also need a waveform monitor to set these levels
properly. Unfortunately, I don't remember exactly which controls are
used. I suggest that you contact your nearest (see yellow pages)
professional/industrial dealer for Sony, Panasonic, JVC or
Ikegami. (Note that some dealers are _box houses_ and some actually
know something. A consumer dealer will be of no use as these
controls are not present on consumer equipment.) 

Jim Winer ..!lzfme!jwi 

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