Path: utzoo!dciem!client2!king
From: king@client2.dciem.dnd.ca (Stephen King)
Newsgroups: comp.sys.sgi
Subject: Re:  videotaping from the iris
Message-ID: <1173@client2.dciem.dnd.ca>
Date: 4 Nov 88 20:49:18 GMT
Article-I.D.: client2.1173
References: <8811020355.aa14353@SPARK.BRL.MIL>
Reply-To: king@client2.dciem.dnd.ca (Stephen King)
Organization: D.C.I.E.M., Toronto, Canada
Lines: 18

In article <8811020355.aa14353@SPARK.BRL.MIL> phil@BRL.MIL (Phil Dykstra) writes:
> [...] You get the lower left hand corner of the screen
>(~640x480 pixels).

I must confess, I am somewhat confused by this. Admittedly, we have not run
our IRIS at NTSC rates for some time, but I am sure that such S/W as the
ARCH demo produced a full screen. Could it depend on the model ? (ours is
an old 2400)

> [...] Why is because the SGI
>board outputs a fully positive video signal (i.e. blanking is around
>+0.3V) rather than a bipolar signal with blanking at 0VDC. 

Have you tried AC coupling the thing with some large capacitors?    :-)

-- 
  {utzoo|mnetor}!dciem!zorac!dretor!king  or  king%dretor@zorac.dciem.dnd.ca
  Stephen J King   =-=   DCIEM Human Factors Division   =-=   (416) 635-2149