Re: Transcribing Music Box Disc
By Robbie Rhodes
At 9:33 AM 10/2/96, Gerard Arkenbout wrote:
> Robbie,
>
> Your email to Jack (John C. Kane) mentions an experiment in the
> future with 2 dimension imagery, to get a precision better than
> 0.003-inch or < 0.1 mm near the edge of the disc. This is a great
> challenge, for how is that to be done for a 20-inch diameter
> metal-disc for the CHORDEPHON-60 music-box. We prefer the DIAZO
> sunlight-amonium hydroxide-vapor method, for the paper stays dry, so
> the exposure is the right image of the disc. With a metal puncher a
> copy of the disc, with the aid of this print, is a very good one. Also
> the exchange of music titles will be an easy one. Because the DIAZO
> copy can be send by letter (not electronically) to the party
> interested. While a flatbed-scan may be transferred to paper, the
> printer will change the dimensions of the image by heating or wetting
> the paper with the exposure. Therefore another electronic transfer
> method must be applicated. (may be a mathematical correction
> during printing, for the dimensions to be achieved are known)
>
> With regards Gerard Arkenbout from the Netherlands
Dear Gerard,
The end-result of my experiment is a computer file which contains all of the information necessary to punch an exact duplicate. Therefore the computer file may be considered the "Master File" for that song-arrangement. Furthermore, the music may easily be modified for smaller, or larger instruments. For example, the computer file for punching a large music box arrangement could become -- with a bit of modification -- the master file for a new Chordephon Zither disc.
I admit that it will not be possible to attain 0.1 mm resolution with a 20-inch disc -- it will be difficult to achieve with the 9-inch Stella disc!
While a small disc image may be made with photographic paper, I agree that the best method for larger discs is the Diazo/ammonia method. It will be necessary to cut the paper image into narrow segments, in order to fit in an 8.5-inch flatbed scanner. Then the computer files must be "stitched together"; fortunately standard software programs are availble for this task.
You are correct: mathematical corrections may need be applied in the case of elliptical distortion.
Best regards,
Robbie Rhodes
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| Robbie Rhodes |
| Return-Path: rrhodes@foxtail.com |
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(Message sent Thu 3 Oct 1996, 00:27:55 GMT, from time zone GMT-0700.) |
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