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Decent Video Recording 60 years old

 
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Decent Video Recording 60 years old

Post by Michael Watterson » Wed May 04, 2016 5:31 pm

Ampex launched their rotating head machine in 1956

An article for 50th Anniversary
http://www.tvtechnology.com/news/0002/t ... -50/184554

BBC "VERA" and Bing Crosby were earlier, but not practical.
1930s video recording only worked on low resolution TV, like the 22 line mechanical Victorian TV promoted by Baird. Some home recordings made on machines intended for music survive.

An updated version of that article was given here recently
http://www.earlytelevision.org/2016_convention.html

 
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Re: Decent Video Recording 60 years old

Post by nuvistor » Wed May 04, 2016 7:15 pm

A page from Tele Tech magazine courtesy of American Radio History.
Attachments
image.jpeg

 
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Re: Decent Video Recording 60 years old

Post by Cathovisor » Wed May 04, 2016 7:38 pm

Michael Watterson wrote:1930s video recording only worked on low resolution TV, like the 22 line mechanical Victorian TV promoted by Baird.

You of course mean 30 lines, Michael :qq1

 
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Re: Decent Video Recording 60 years old

Post by Michael Watterson » Wed May 04, 2016 10:27 pm

Wasn't the original Victorian gadget 22 lines?

Anyway, while Baird created a buzz and his wet film scanner idea was used in satellites eventually (as the exposed film could be developed and then slow speed scan of film transmitted to Earth), the Electronic TV was always going to "win", the difficulty known from 1905 to be the material for camera target and how to read off the charge with crt beam. Farnsworth's method was doomed as it only reacted to the light the instant as the dot is scanned, whereas the Zworkin (RCA / EMI) method the "pixel" reacts to light for entire frame, thus 10,000 more sensitive, and even more difference as resolution is increased.

Interesting that the rotary head was first investigated for HiFi audio in 1938, I didn't know that, I thought it was invented for video. What made tape work for video was using an FM carrier. At the high tape to head speed it solved amplitude variations and also solved the frequency response equalisation issue, reducing 18 octaves to 3. We learnt all about it on one of the BBC courses.
I got to "play" with 2" VCR once. In the late 1970s I worked on / repaired / services or used Umatics, 1/2" EIAJ reel (desktop and portable, B&W and one with colour under), pansonic cartridge, one crazy 1/4" Akai reel to reel (colour), 1500 & 1700 meccanno kits (AKA Philips), VHS, Betamax and one RCA VHS for security with a stepper motor for tape transport for low frame rate security recording. The V2000 finally staggered (2 years late?) into production just as I left the industry to go into computers, so to this day I've never seen one in real life, only in photos. It's very clever and if Philips had figured how to mass produce the machine (likely the head was a problem) at same time as VHS and Betamax, who knows what might have happened.
The 1500 etc tended to stop working if you didn't be gentle moving them. The ones in schools & colleges kept us busy, the ones that were never moved were fine.
People tended to break the heads on EIAJ open reel machines, comparatively we hardly replaced heads on the cartridge and cassette type machines.

There was even a digital video version of VHS (never took off as both HDD recorders and DVD recorders arrived) and also a variant of Betamax as conputer backup drive.

Was there ever a recordable Laser disk? I saw a demo in Belfast just after launch, and then years later (late 1990s?) I sorted problems on a computer based training system in De Beers, Shannon that used Laser Disk as source for interactive video. I have two CDi videos (not quite white book I think and poor quality) and a few Video CD (Much better but poor compared to DVD). By 1999 you could make you own VCD at better quality that the original Star Trek VCD commercial release due to how much the MPEG1 encoding had improved.


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