Electronic projectors for theaters in 1940
David
In 1940, RCA electronic projectors for movie theaters:
http://www.earlytelevision.org/rca_theater.html
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Time line:
First RCA rear-projector was introduced in 1946 (!)
http://www.sid.org/archives/0%20-%20Projection%20pdf%20Exhibit%204.pdf
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"Eidophor" projectors used a thin layer of transparent oil on an aluminum
mirror, reportedly _still_ have stunning images. On some, the frame was
refreshed by scraping the oil surface smooth.
"If the size of the spot on the oil is adjusted such that adjacent lines
just begin to overlap, the charge is distributed uniformly over the whole
area, the pressure on the oil is uniform, and no deformations are generated.
If the size of the electron spot is narrowed, the charge distribution is no
longer uniform, but reflects the TV line pattern, as does the resulting oil
layer deformation. The smaller the spot, the deeper will be the
deformation."
http://www.spgv.com/columns/eidophor.html
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Japanese Muse HDTV was demonstated here in the USA in the early 1990's
using three-piece General Electric "Talaria". It weighed 600 lbs, used 50
amps @ 234 Volt, needed 20 minimum warm-up time and had horrendous
maintenance issues.
http://www.hi-def.com/3LV.html
"In the Talaria, the oil film is made by rotating a glass disc, with a
conductive surface, which dips into an oil bath and picks up its coating.
Like the Eidophor, when no charge is projected onto the oil film by the
electron gun, all light is blocked by the Schlieren stop. In this case the
green component is blocked by horizontal bars and the magenta component by
vertical bars. When the image is projected via the electron beam onto the
oil film, it deforms and reflects light past the Schlieren stop into the
lens".
These types are still found on ebay now and then, I'd love to get one and
play with it.
I think that was the design that led to the CRT-addressed ILA panels made by
Hughes, then becoming JVC-Hughes, and now pushed further along by Sony with
the SXRD/LCOS "Ruby" projector. [VPL-VW100. ~$8,500, street].
Amazing unit and yes, I want one.
wbertram
wonder what these great pioneers would think of today's offerings?
rjn
mention several types of projection TV, including
5TP4-based (with some detail), Eidophor and Scophony
(with no detail on the latter two).
It even claims there was a system based on kinescoping
a TV monitor at the theater, filming that, developing and
drying the film, and projecting it, all as a continuous process.
I wonder if today's 35mm theatres will get converted to
digital, or if theatrical exhibition will implode first.
--
Regards, Bob Niland mailto:na...@ispname.tld
http://www.access-one.com/rjn email4rjn AT yahoo DOT com
NOT speaking for any employer, client or Internet Service Provider.
Grant Edwards
> The 1954 edition of "Basic Television" (Bernard Grob) mention
> several types of projection TV, including 5TP4-based (with
> some detail), Eidophor and Scophony (with no detail on the
> latter two).
>
> It even claims there was a system based on kinescoping a TV
> monitor at the theater, filming that, developing and drying
> the film, and projecting it, all as a continuous process.
Now _that_ I'd like to see!
--
Grant Edwards grante Yow! YOW!! I am having
at FUN!!
visi.com
David
news:1136332722.7...@g43g2000cwa.googlegroups.com...
Webpage on Scophony:
http://www.tvhistory.tv/1938-Scophony-UK.htm
Talk about a spinning color wheel . . . fascinating.
Richard
were not very pleasing on such a large screen, even at 525 scan lines. I
guess WWII got in the way of further developments.
Richard.
Matthew Vaughan
> digital, or if theatrical exhibition will implode first.
http://www.marketwire.com/mw/release_html_b1?release_id=105112
http://www.christiedigital.com/corporate/news/index.asp?SortType=market&SortOption=15#list
David
news:43bdccb3$0$95928$742e...@news.sonic.net...
I'd like to see one of these Sony 4096 x 2160 units in a theater.
rjn
> I'd like to see one of these Sony 4096 x 2160 units in a theater.
> <http://news.sel.sony.com/pressrelease/4864>
That is the sort of thing theatrical exhibition needs to do:
differentiate against HDTV, as widescreen did against
SDTV back in the 50s. But that won't necessarily assure
sustained success. Many experiments in differentiation
failed then. Routine 70mm 5-perf exhibition is gone today,
for example.
4K x 2K is arguably a major improvement over existing 35mm
exhibition. Although 35mm is theoretically capable of near
that resolution, I doubt the average screening gets to even
half that due to generational loss, less than optimal focus,
registration jitter, film weave, not to mention sub-SMPTE
illumination levels.
IMAX (70mm 15-perf) promotes its resolution, and survives,
but it's carved out a niche market.
I'm predicting that HD-DVD/BR will be a niche format, as
LaserDisc was (1% share), but if I'm mistaken, and HD
takes root in the home, it may kill theatre exhibition.
For decades, VHS-SLP over an RF connection was
"good enough" for the mass market. DVD over YPbPr
is dramatically improved over that, and more than
satisfactory as a theater alternative for many. HD on
home media probably exceeds the experience in the
local 35mm sardine can.
Whichever way it goes, it will be interesting to watch
develop. Pass the popcorn.