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-   -   Remember Sylvania's Slide Scanner TV? (http://www.videokarma.org/showthread.php?t=251575)

Mal Fuller 07-08-2011 06:31 PM

Remember Sylvania's Slide Scanner TV?
 
I sold one of these new - tough sell.
http://i573.photobucket.com/albums/s...t62357PM-1.png
http://i573.photobucket.com/albums/s...8at63022PM.png

Sandy G 07-08-2011 06:56 PM

How did it, erm, Work ?

leadlike 07-08-2011 07:11 PM

Flying spot scanner picked it up for reproduction onscreen. For the extreme cost to go this route, not a lot were made. The only other FSC designed for consumer tv that I can think of is the Kodak VP-100, which transferred super 8mm film in real time to video. I've never seen one of these Sylvanias working, so no idea what the picture quality was like. The Kodak's was certainly passable for SD analog.

Mal Fuller 07-08-2011 08:10 PM

The quality of the slide reproduction was on a par with a good over the air broadcast.

old_tv_nut 07-08-2011 08:41 PM

Quote:

Originally Posted by Mal Fuller (Post 3008538)
The quality of the slide reproduction was on a par with a good over the air broadcast.

Agree - we bought one for evaluation at Motorola when I worked there. Most frustrating thing was that slides are 1.5:1 aspect ratio, so left and right sides of the picture were cut off by the 1.33:1 picture tube. They did not offer an optional "letter box" mode. Plus, with the usual overscan, some of the top and bottom were lost too. For a long time, TV manufacturers avoided black bars like the plague, since they would result in service calls.

jr_tech 07-08-2011 09:01 PM

Did the scanner CRT use a short persistence white phosphor, like P-45 perhaps? And three pickup PMTs/photodiodes with color filters? Color wheel? Perhaps lower frame rate?... How did the system work?
jr

old_tv_nut 07-08-2011 09:07 PM

3 PMTs. Can't recall if the phosphor appeared white or greenish to the eye. I know some RCA catalogs listed a color FS CRT that appeared greenish to the eye.

Edit - found the 1958 catalog - lists 5AUP24 "Intended primarily for use as a scanner in a color video-signal generator. Feature useable radiant energy output over the visible spectrum, extremely short persistence..."

"Phosphor P24 is a short-persistence phosphor with green fluorescence and phosphorescence. Its spectral-energy emission characteristic has sufficient range to provide useable energy over the visible spectrum requried for generating color signals from color transparencies."

jr_tech 07-08-2011 09:43 PM

Cool! THANK YOU! I didn't think about the greenish P-24 being useful for a 3 color application.
jr

old_tv_nut 07-08-2011 09:54 PM

Sylvania was into phosphor research, of course, so the phosphor used may have been their own special concoction.

bgadow 07-08-2011 10:08 PM

From what I've seen in trade magazines from that era, the "Gibralter" tv chassis used in these Sylvanias was highly regarded. I haven't read up on it much, but it was a hybrid, I guess? I know they had an all-solid state color chassis around this time; maybe that would have pushed the price way off the map.

old_tv_nut 07-08-2011 10:14 PM

1 Attachment(s)
here's some more info on FS film scanners

Mal Fuller 07-08-2011 11:26 PM

Quote:

Originally Posted by old_tv_nut (Post 3008547)
Agree - we bought one for evaluation at Motorola when I worked there. Most frustrating thing was that slides are 1.5:1 aspect ratio, so left and right sides of the picture were cut off by the 1.33:1 picture tube. They did not offer an optional "letter box" mode. Plus, with the usual overscan, some of the top and bottom were lost too. For a long time, TV manufacturers avoided black bars like the plague, since they would result in service calls.

The conflict of aspect ratios never crossed my mind and slides seemed to be presented well on the CRT. But your point is take as some compromise had to be necessary.
It's interesting that it generated enough interest to warrant Motorola's investigation. The public was certainly disinterested. My shop and salesroom were located in Wolfeboro New Hampshire, but the guy I eventually sold mine to lived in Berwick, Maine.

kx250rider 07-09-2011 11:20 AM

I've had two of them; none working. Very rare set by now!

Charles

Jeffhs 07-09-2011 01:13 PM

I never saw one of these sets in person, but I did read a review of one in Popular Science magazine in the late '60s, just when they were appearing on the market. The set used a Kodak Carousel slide projector with a flying-spot scanner, and the necessary circuitry to convert the output of the latter to NTSC video.

Today's DVD players can read almost any type of CD, even photo discs and those made from floppies, so if you have one and a color TV, you will have the 21st century equivalent of the Sylvania set we are discussing here -- and you don't need a living room the size of Texas to put the system in (the Sylvania set is in a huge console cabinet). I have successfully viewed photo CDs using my Memorex DVD player, and the pictures look very lifelike, probably much sharper than images any flying-spot scanner could produce.

I was not aware of the aspect ratio discrepancy problem (1.5:1 -> 4.3) with the Sylvania color-slide theatre TV. How much would it have added to the price of an already expensive system like this to correct the aspect ratio to 4:3 when slides as well as TV were being viewed? I am not talkng about letterboxing or any other technique as used for today's HDTV; rather I am referring to a system that would create a 4:3 picture on a standard TV screen from the output of a flying-spot scanner.

old_tv_nut 07-09-2011 04:01 PM

Quote:

Originally Posted by Jeffhs (Post 3008601)
I am not talkng about letterboxing or any other technique as used for today's HDTV; rather I am referring to a system that would create a 4:3 picture on a standard TV screen from the output of a flying-spot scanner.

? Not sure I understand the question. What it did was scan the center 4:3 part of the slide, cropping off the left and right edges.


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