Archived posting to the Leica Users Group, 2001/05/14

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Subject: Re: [Leica]Songs my grain magnifier taught me...Was Konicagate
From: Mark Rabiner <mark@rabiner.cncoffice.com>
Date: Mon, 14 May 2001 11:12:57 -0700
References: <F180G3ESvUC9y3jVON300003e96@hotmail.com> <f0501041bb725381c9175@[195.64.98.82]>

Christer Almqvist wrote:
> 
> >If you REALLY want to find out how crappy your technique is just use
> >a grain focusing magnifier with a fine grain black and white film.
> >
> >You will never again believe there is any such thing as depth of
> >field and you will swear that you have a constant case of the
> >jitters!
> >
> >The point is, very few photographers print thier own stuff and of
> >those that do, a large portion use high speed film almost
> >exclusively.  For these folks most of this discussion is esoteric.
> 
> You hit it on the nail. When I use 400 film I often ask myself: "Why
> did you buy a Leica?"
><Snip> 



Oversampling.
It makes sense in audio and now TV broadcasting (see below). Why would it not
also make sense in traditional still photography?


Mark Rabiner


" People seem to think that high definition television needs lots of lines, but
it's a myth. Cameras and displays need a lot of lines to overcome aperture
effects and to render the raster invisible, but the transmission medium between
doesn't. In the early days of television, the capture, transmission, and display
formats had to be identical for simplicity, but that's no longer true or desirable.

A 480-line camera can't give 480 lines of resolution, but a 960 line camera with
downconversion can. Effectively, the camera is using oversampling. Although
oversampling has totally dominated digital audio because of its obvious merits,
it is harder to use it in conventional television because of interlace.
Interlace puts half the picture data at another time and reduces the performance
of spatial resamplers. Once interlace is dispensed with, oversampling becomes an
obvious and attractive technology."

In reply to: Message from "Dan States" <dstate1@hotmail.com> ([Leica]Songs my grain magnifier taught me...Was Konicagate)
Message from Christer Almqvist <christer@almqvist.net> (Re: [Leica]Songs my grain magnifier taught me...Was Konicagate)