Years ago I did a study on this very topic for the Library of Congress.
What I found was that when the groove was not played, it was used to guide
the reading head. There was no contactless playback available.
Electron microscope scanning is one solution. It requires the device to be
programmed to read vertical grooves rather than later ones and may need to
deal with the different colors of cylinder materials. I don't know what
progress may have been made in this regard recently.
Steve Smolian
-----Original Message-----
From: Association for Recorded Sound Discussion List
[mailto:[log in to unmask]] On Behalf Of George Brock-Nannestad
Sent: Sunday, April 01, 2012 6:00 AM
To: [log in to unmask]
Subject: Re: [ARSCLIST] contactless reading of cylinder negatives, WAS Fw:
[NMC]Alan Lomax's Massive Archive Goes Online
From: Patent Tactics, George Brock-Nannestaed
Hello Joe,
my previous comment was somewhat garbled, so here I go again and with an
important technical addition.
- indeed, someone made equipment, and it was aimed at the many, many copper
negatives held by the Phonogramm-Archiv in Berlin. It was an experiment
described (with photographs) in the following article:
Gerd Stanke and Thomas Kessler: "Procedure to Recover Sound Signals From the
Negative Tracks in Copper Negatives of Edison Cylinders in an Image
Analysis/Sensorial Way (SpuBiTo)", in (Arthur Simon, Ed.) 'The Berlin
Phonogramm-Archiv 1900-2000. Collections of Traditional Music of the
World.', VWB - Verlag für Wissenschaft und Bildung, Berlin 2000, pp.
209-215.
The main problem was one of fitting the distorted microscope images to a
long string of non-distorted images. At the time, the scanning time was 80
minutes for one cylinder negative. However, there is presently a product
offered by the developers GFaI (Gesellschaft zur Förderung angewandter
Informatik e.V.); try to google the strange word "SpuBiTo" - today I had 135
hits.
Now, when I wrote the above I thought that the process was contact-less.
Studying the GFiI brochure at first I thought that a diamond stylus they
mention rides between the ridges to define where the grooves are. However,
reading the text in view of the 2000 article mentioned above, I am now
convinced that the stylus actually rides on the top of the ridges,
controlled by the image capture, so that is is a mechanical tracking after
all. It is a vertical position measuring system. It is very gentle
mechanical tracking, but it is then much more similar to the Kyiv system
used for ordinary cylinders.
Hence, we still only use part of the information content in these ridges
(i.e. originally grooves).
The background noise from copper negatives would have two sources.
1) from the metallisation of the original - not all used the Edision
gold-sputtering process
2) from the galvanotypic process: if your deposit current was too large, you
would have large crystals, and the edges would make a noise. The rule was
"start slowly, to build a quiet layer, and then increase the current to
build thickness". However, if you were in a hurry - - - - -.
Not to mention that sometimes the researchers at the Berlin archive played
the cylinder before the galvano process - - - -
Best wishes
George
----------------------------------------
> So galvanos were used to make cylinders but were not themselves
> reproducible, unlike metal parts for a disc.
>
> Or did someone design a machine to play them? It would be fascinating
> to hear a cylinder recording made from metal parts, assuming that they
> would be as quiet as their disc counterparts.
>
> joe salerno
>
> On 3/29/2012 10:38 PM, Michael Biel wrote:
> > On 3/29/2012 4:54 PM, David Lewis wrote:
> >> BTW the galvanos used by the Berlin Phonogrammarchiv to mass
> >> produce copies of ethnological cylinders were, in effect, metal
> >> cylinders. But they represented the negative image of the groove,
> >> and the grooves
> themselves
> >> were inside the galvano. Dave Lewis Lebanon, OH
> >
> > Of course that is how ALL mass produced cylinders were made. I have
> > a metal mould that was used to make one of the Ediphone Dictation
> > lesson cylinders as late as the 1950s.
> >
> > Mike Biel [log in to unmask]
> >>
> >> On Thu, Mar 29, 2012 at 9:49 AM, [log in to unmask]<
> >> [log in to unmask]> wrote:
> >>
> >>> Metal cylinders? Someone please tell me more about these. Who made
> them
> >>> and when?
> >>>
> >>> joe salerno
> >>>
> >>>
> >>> On 3/29/2012 7:30 AM, Chris J Brady wrote:
> >>>
> >>> Throughout his career, Lomax was always using the latest
> >>>> technology to record folk music in the field and then share it
> >>>> with anyone who was interested. When he started working with his
> >>>> father, John Lomax, in the '30s, that meant recording on metal
> >>>> cylinders.
> >>>>
> >>
> >
>
> --
> Joe Salerno
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