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  #16  
Old 03-21-2017, 04:34 PM
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If you mentioned H.D. tube cameras, I'm curios how the image provided by one is.
In Europe we had "Bosch" KCH 1000. Plumbicon and saticon. Never seen images taken with one.
B.t.w., some tube cameras had very vivid colours, which I like. On youtube I've seen only C.C.D. camera (an 1989 "Sony") with vivid colours.
Can you find Betacam (not Betacam S.P.) cassettes today?
And can you plase post some images filmed witn your "Sony" BVP-30. Dind't saw on youtube any filming wiht one such camera.
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  #17  
Old 03-21-2017, 05:54 PM
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Quote:
Originally Posted by Telecolor 3007 View Post
If you mentioned H.D. tube cameras, I'm curios how the image provided by one is.
In Europe we had "Bosch" KCH 1000. Plumbicon and saticon. Never seen images taken with one...[/B]
BTS was the joint venture of Bosch and Philips.

https://en.wikipedia.org/wiki/Broadc...on_Systems_Inc.

The color performance of HD and SD Saticon cameras is not theoretically different. It depends on the design of the color splitting prisms, which could be the same, the response of the Saticon photoconductor, which was the same, and the color matrix, which could be the same. The resolution of the Saticons was an issue, however, and special HD Saticons with smaller beam size and smaller cathodes were made for HD. This made the predicted life of the HD tubes shorter, and they were only guaranteed for several hundred hours. We did a preemptive tube replacement on our camera at about 800 hours, but there was really no sign of degradation at that time. Compared to later solid-state chip cameras, the tube cameras were noisier, as the faceplate is capacitive, producing a 6dB per octave roll-off. This is compensated by feedback increasing gain by 6 dB per octave, also producing a triangular noise spectrum, so the wider bandwidth of HD increased the noise greatly. Fortunately, the eye is less sensitive to high frequency noise, so the effect was not as bad as indicated by the total noise power.
Nevertheless, the video preamplifiers were limited in frequency response to about 22 Mhz instead of the 32 MHz required to get full horizontal resolution.

Chip cameras, on the other hand, generally have a flat noise spectrum (and less noise over-all), produced by the charge-counting noise of the pixels plus the semiconductor dark noise.

The small spot size also meant limited beam current, so the HD cameras were more subject to highlight overload and "comet-tailing" than SD cameras. The HD Saticon cameras used bias lighting to reduce lag, just as the SD cameras did, and showed the same effects of lag being different for highlights, midtones, and shadows (worst in shadows).
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  #18  
Old 03-21-2017, 08:14 PM
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800 hours... man, that about 3 month of camera use. But if they needed more pixels, why they didn't made the tubes bigger, so they could have the same number of "pixels", but larger ones so the tubes could last longer, much longer.
But S.D. camera tubesc last longer, no?
And what is that "comet-tailing effect"?
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  #19  
Old 03-21-2017, 09:06 PM
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Comet tailing is the long persistence of very bright highlights due to insufficient beam current to discharge the photosensor in one TV field.
Here's an example:
https://www.youtube.com/watch?v=l4qamJ1cDfo
Edit: common places to see this were on brass band instruments and women's jewelry or sequined dresses.

Saticons, Plumbicons, and similar tubes have the problem. Special design changes were made over the years to reduce it: diode electron guns, which produce cathode rays with a lower variance of electron velocity (a lower "temperature"); plus special circuits that sense the highlight and momentarily increase the beam current (but reduce the resolution momentarily also).

And yes, SD camera tubes lasted longer.

I think the reasons for not making larger tubes were several, all having to do with increased cost: entirely new and bigger lenses (TV cameras already needed special lenses with long back focus to pass the image through the long path in the prism block); new larger prism blocks; possibly, difficulty in making larger faceplates/targets with good uniformity (requiring new manufacturing equipment as well). Also, a larger faceplate would have more capacitance, making it harder to get the high frequency response needed.

I will note that due to the smaller image size than 35mm film, the depth of field was increased compared to film. It was hard to sell HD as a movie making technology, because cinematographers felt they had plenty of depth with 35mm by using a smaller lens opening, and wanted the capability to reduce depth of field and blur the background more in many shots.
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  #20  
Old 03-21-2017, 09:58 PM
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Thanks to all for contributing to this tube camera thread. Great info coming in. Plumbs and Saticons were the day. I have my fav as you know. Keep up the great info on these great cameras...for all of us that remember them. I found my VA-5 adaptor today. Hooray, if I pull my deck from the camera I have a record only deck that can input analog in the field from some other source. Now I can copy my DVD's to Beta!
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  #21  
Old 03-21-2017, 11:20 PM
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Another thing about Plumbicons, Saticons, and such:

As the beam scanned the target, in almost all areas (except those pesky comet-tailing highlights), it had more than enough total current to discharge the target. This means that the charge would be neutralized by just the leading edge of the beam (a variable portion due to the varying charge level). So, the effective beam shape wasn't nice and symmetrical, but actually was a crescent shape. The beam was also partially discharging the next lower scan line, so the crescent was like an arc with the center toward the lower right and the pointy ends more up toward the right and down toward the bottom. This effect was called "beam sharpening," and resulted in the resolution for lines and edges slanted from lower left to upper right being better than for lines slanted the other way. A really fancy camera CCU would have a two-dimensional detail enhancer (using analog delay lines, or later, digital processing) that would allow independent adjustment of the detail sharpness for left-slanting and right-slanting lines.
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  #22  
Old 03-23-2017, 03:43 PM
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CEI color camera brochures and prices from 1979.
Cameras designed for field use plus expansion for studio use.

Anyone familiar with this brand?

http://www.bretl.com/tvarticles/docu...10brochure.pdf

http://www.bretl.com/tvarticles/docu...0infosheet.pdf

http://www.bretl.com/tvarticles/docu...330adsheet.pdf

http://www.bretl.com/tvarticles/docu...aPriceList.pdf
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  #23  
Old 03-29-2017, 07:05 PM
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Wonder if you can do a live on facebook with one.
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  #24  
Old 04-04-2017, 05:19 PM
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80s tube cams fun

Wayne has done an excellent job outlining the problems of tube cameras for HD.

The first time I saw an HD (1125 line) camera was at the SMPTE Winter Conference in SFO in 1981, made by Ikegami and using Saticon tubes. The resolution was quite good, but the noise was obvious. Later, while at NBC, we purchased a 30mm lead oxide (PBO) camera, also from Ikegami, and this camera did not suffer the image retention of the Saticon camera, and seemed to have much improved noise performance.

I believe that the lead oxide tube operated at higher signal current, but it likely had a much improved FET head amplifier. In addition, some manufacturers played games with the gamma corrector near black by placing a reverse correction that clipped the noise. It was not correct, technically, but subjectively, it was much quieter.

Wayne mentioned the special FET from Sony (?) that was sought by RCA for its cameras, but they would not sell it to a non-Japanese manufacturer.

In the late 1980s, there was a desire in the US and Europe for a HD production standard other than 1125 interlaced, such as the Zenith 787.5 line system. Hats off to them. I recall RCA Laboratories telling NBC the next TV standard has to have two attributes-component coding and progressive scan.

So NBC, AT&T, and Zenith bought Bosch KCH-1000 flexible standard cameras with Saticons. By changing dip switches and many ROMS, you could operate the camera in interlace or progressive. The complete camera, including image enhancer, was almost $500K. I wrote the PO, and no one flinched.

AT this time, Bosch and Philips merged their broadcast divisions, and camera development moved from Darmstadt to Breda. There was a lot of bad blood between the two engineering staffs, so assistance from the new company was a problem.

Noise from the Saticon camera was always an issue, especially when the signal was sent to an MPEG encoder. We generally ran the camera at the lowest sensitivity possible-minus 6 dB. But the pictures were high in resolution.

Later in the evolution of tube cameras, the diode gun tube was introduced to improve resolution. That it did, but only static resolution. The beam size was so small that it was inadequate for the complete discharge of a 525 scan line picture. The net result was an after image on moving, high contrast scenes known as "stern waving." I recall seeing the actor Danny DeVito in white shirt and tux performing in front of a diode gun equipped camera-the image resembled an unterminated delay line or coax, but it was moving with the scene.
The best advice about pickup tubes came from Bob Neuhauser of RCA-the electron optics of a tube must match the scanning standard. He was so right.
This was all so long ago, but it seems like yesterday.

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  #25  
Old 04-04-2017, 05:47 PM
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Quote:
Originally Posted by J Ballard View Post
So NBC, AT&T, and Zenith bought Bosch KCH-1000 flexible standard cameras with Saticons. By changing dip switches and many ROMS, you could operate the camera in interlace or progressive. The complete camera, including image enhancer, was almost $500K. I wrote the PO, and no one flinched.

JB
A few more notes on the KCH-1000. It was very flexible, but not quite enough for the progressive scan. The viewfinder could not run at 47kHz horizontal and had to be redesigned. Also, the digital control circuits ran at 27 MHz. These took special high speed (for the time) CMOS ICs, so we had to buy them only from Philips to have stock for any repairs.

Zenith and their partner, AT&T each bought a camera, and with the modifications we were charged $800k apiece. These cameras also followed the same practice as Sony and others at the time, of reducing the video bandwidth to 22 MHz or so to reduce the noise, but we needed 32 MHz to get sufficient H resolution with progressive scan. We immediately discovered the 27 MHz digital clock and control signals were running all over the chassis, and spent a lot of effort adding shielding and grounds to get it out of the video.

We also had to design and build our own aperture corrector/edge enhancer to work with the progressively scanned signal.

Fun!
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Old 04-04-2017, 06:08 PM
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Half a milion U.S. Dollars for a televison camera?
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Old 04-04-2017, 10:06 PM
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Quote:
Originally Posted by Telecolor 3007 View Post
Half a milion U.S. Dollars for a televison camera?
Bleeding edge prototypes ain't cheap if you adjusted for inflation the money RCA spent on any part of the NTSC color standard back in the early 50's those HD cameras would not look that expensive...
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  #28  
Old 04-05-2017, 02:16 PM
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80s tube cams fun

Once we got the HD cameras operating in the desired standard (1050i/59.94 or 787.5/59.94), we had to connect the camera to other equipment-sync gens, distribution, test signal gens, VTRS). In the late 1980s, reference signals could be H&V drive, tri-level, or bi-level-there was no one standard.

Recording/editing meant using the Sony HDD-1000 digital R-R VTR, but it would only work on 1125/60. NBC and others tried ordering a VTR that would operate on other standards, but Sony said no, presumably not wanting to upset NHK. So we ordered the VTRs anyway, and said we would modify them; that would void the warranty, they said. I believe they were $300K each and the tape stock was $1500/reel. NBC ordered two, and Zenith and others ordered some, and modified them in house, despite loud protests from Sony.

To be fair, Bosch had an analog HD VTR, but based on earlier experience with the HDVS Sony system, analog machines were noisy and had poor K factor.
Bosch later married two D-1 VTRs together and were able to record 1440 pixels per line, similar to HD Cam much later.

The HDD-1000s suffered from head clogging, despite the installation of a razor blade "cleaner" in the tape path. If you were unaware of this feature, you could injure your fingers. There are some surviving machines at the Museum of Broadcast technology in Woonsocket, RI. Staff from the Museum will be at NAB this year, so stop by.

You cannot imagine the political headwinds against progressive scan, and I have enduring respect for Zenith and others such as Kerns Powers of RCA Laboratories who had patents on 720P. Another was Tony Uttendayle (SP?) of ABC and yet another Jukka Hammalinen of Panasonic The Japanese publicly were against anything other than 1125/60, and even tried to convince the Europeans to drop 50 HZ. One thing the Japanese did not understand in the emerging HD debate was the powerful influence of the computer industry in the US, and they naturally wanted pro-scan and square pixels; they got the latter.
Eventually, Panasonic broke the log jam with their D-5 HD VTR which had 720P mode buried in the menus. Later, they made 720P cameras that ABC used on "Monday Night Football." BTS made a 720 P CCD camera, and soon thereafter, there were switchable standard cameras from Breda using their 9MM pixel DPM sensor. The Japanese finally began making multi standard equipment.
One thing about UHD-it will sink the interlace/progressive argument for good.

Thanks Wayne for the comments on the KCH-1000 mods.
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  #29  
Old 04-05-2017, 03:28 PM
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Regarding recording progressive scan on the HDD-1000, Zenith didn't modify their HDD-1000, but used the "Format Converter" devised by Charlie Rhodes (formerly Tektronix, and head of the Advanced Television Testing Center at the time). This device segmented each frame into rectangular pieces and fit the pieces into the Sony image format for recording, and then reassembled the progressive frame on playback.

This device was used for all the test material in all proposed formats at the ATTC so they could use unmodified Sony tape equipment.

The Sony tape heads were very sensitive to contamination and wear, and we were constantly monitoring the signal quality, having to replace the heads several times over the years of testing. Later, in the 2000's, when we were in new facilities, smoke from some burned food in the kitchen appliance division got into the ventilation system. It was just a nuisance smell for our employees, but it clogged the Sony heads, which had to be replaced.

Before the HD tape machines arrived, Zenith's work on HD used a frame store that could hold 10 seconds of HD material. The semiconductor memories at the time required a 6-foot tall rack to hold enough chips for 10 seconds of video, and cost several hundred thousand dollars in itself.
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Old 04-05-2017, 09:11 PM
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My thanks to all of you for a great thread that started with a simple note to plumb owners of the Sony cameras of the early Beta era. What has happened is a great history of all of the HD efforts and the cams of the era. Keep it going and don't worry about my original. Your knowledge goes well beyond my question and is welcome.
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