3D effect on old videofilmings

[Telecolor 3007]

I've noticed in some old filmings that the image had a kind of 3D effect. They where low rezolution images (including one filme with an '000's portable amateur videocamera). Example (both black and white and color): https://www.youtube.com/watch?v=f-5B9cM2XyI
Here you can notice a little bit too: https://www.youtube.com/watch?v=KF_9wRVnazQ
But I've noticed in some old H.D. images too: https://www.youtube.com/watch?v=b0yIDZz6OnA

I wonder what generated this effects?

[old_tv_nut]

In the SD sequences, you are seeing a combination of lighting and transient response (the speaker at the podium) or just mainly transient response (video detail peaking and video tape phase response) in the musical sequence. In the HD test scenes, I see very little of these effects, mainly just an increase in detail.

While I was working as an engineer for a TV maker, we had an independent inventor try to sell us on using his patent for a 3-D bas-relief effect. It was simply a phase distorting circuit that put an opposite phase smear to the right of everything (a white area on the right edge of black objects and a black area on the right edge of light objects).

We rejected the idea, as it was really a phony effect that you would get tired of quickly; plus it obscured some details while enhancing others; plus, manufacturers worked hard to eliminate this effect when it occurred due to phase delay in the IF circuits; plus it was something that should have been rejected by the patent office as obvious to skilled practitioners.

[old_tv_nut]

By the way, that broad sort of peaking that the inventor was proposing was adopted in a refined form for home VCRs, to make the pictures look sharper although they had poor high frequency detail. In multi-generation VHS or beta copies, this gets way overdone, which you can see on on old bootleg copies of Star Wars and other old home-taped stuff that is posted on Youtube.

We have one guy here who is crazy about these old analog failings - each to his own taste, I guess.

[jr_tech]

I think that the shallowness of the depth of focus adds to the effect, as well... makes the foreground images really stand out.

jr

[old_tv_nut]

Originally Posted by jr_tech

I think that the shallowness of the depth of focus adds to the effect, as well... makes the foreground images really stand out.

jr

Yes - I didn't think about that. A tried and true photographic/cinematic technique. In fact, when HDTV first became available, and Sony was proposing using it for producing movies, the complaint from many cinematographers was that it had too much depth of field (due to the small size of the sensors and corresponding small physical dimension of the lens aperture for a given f/ number). They could not get the background to be as blurred as they wanted.

[Adlershof]

Originally Posted by Telecolor 3007

I've noticed in some old filmings that the image had a kind of 3D effect.

You could call it analogue sharpening. Plumbicon cameras had circuits for that (you may find the more-less control for them labelled "contour"), IO tubes had such an effect naturally (the one that produced the infamous dark halos around bright lights).

Beyond that it is a really nice selection of videos you brought up here.

The first one is the real start of West German colour TV, also half a century later still considered big fun for having the colour burst thrown in way too early. Cameras were Philips LDK-3 [in North America known as PC-60/PC-70] because Fernseh GmbH had nothing to offer yet in 1967, after their attempts to build a IO colour camera failed (it seems that the main issue was registration, which TV stations declared as unmanageable for the prototypes they tested).

Some people claim that it was simply impossible to build a usable colour camera with IO tubes. Your second video is an example for the results that could be obtained with this impossible approach. (Weight, set-up, sensitivity etc. are another question; the claim was that it would never work at all.)

And your third video shows HD captured with Saticon tubes. Just look out for the streaking on the headlights at 2:30.


VHS: In fact it is a surprise that people had put up with this quality at all.

Depht of field: Image size of 35 mm 1.37:1 is 16x22 mm, not much bigger than on 30 mm tubes. It was frequently obvious to the attentive viewer that focussing on long focal lengths was pretty delicate.

[old_tv_nut]

Originally Posted by Adlershof

IO tubes had such an effect naturally (the one that produced the infamous dark halos around bright lights).

---

VHS: In fact it is a surprise that people had put up with this quality at all.

The IO halo had to be suppressed in color cameras by operating below the "knee" because bright colored objects would have produced complementary-color haloes. Special IO tubes were produced for color that had a higher knee point. In monochrome, operation above the knee was used deliberately, as stated, to enhance edges while providing an approximate sort of gamma correction.

Regarding VHS quality, the old saying is "Content is king."

[old_tv_nut]

Regarding depth of field, I can testify from personal experience with the early HD cameras that accurate focus on a 7 inch viewfinder was nearly impossible. Sony made a great invention in focus peaking for the viewfinder, which makes the high frequencies light up brightly when the amplitude is maximum.

Cinematographers, however, still wanted less depth of field, as they were used to working with precisely calibrated lenses for which the focus could be set by actually measuring the distance with a tape measure and then dialing that in on the lens. An entirely different process from producing live video.

[old_tv_nut]

Here's a good example of the difference between using IOs above the knee and below the knee with explicit gamma correction.

The game program "What's My Line" was broadcast and kinescope recorded in monochrome until 1966. It then went to color, but was still kinescoped in monochrome. The early color tapes were erased, but the monochrome kinescopes of the color shows survive. Compare the rendition in these two episodes:

From color camera with gamma correction (1967):
https://www.youtube.com/watch?v=D52ks7-G0PA

With monochrome cameras operated above the knee (1955)
For example, see at 00:40 the dark halo around the performer and at 01:25 the dark halo around the game box in the picture.
https://www.youtube.com/watch?v=3fKzmCHAWPc

[nasadowsk]

This Quad clip of Jim Reeves shows the IO's haloing effect well at a few spots:

https://www.youtube.com/watch?v=WKLUj892gHY

Also - I'm guessing the wobble in the picture is from orbiters? It looks like at least one of the cameras in the shot was a bit past it's prime....

[old_tv_nut]

The 1963 RCA catalog says that the high end 4.5 inch TK-60 A had both an orbiter and a stabilizer that corrected the image wander due to the orbiting. It says the rate was 1 RPM. The clip you posted has a compensated orbiter, but its rate seems to be faster than 1 rpm. I'm not sure how an orbiter and compensator that are both magnetic works, but it may have something to do with the 4.5 inch IO tube in particular. The info on the 3 inch TK-14 says it has an orbiter, but does not say it is compensated, only that it's not noticeable.

The TK-41 color camera had an uncompensated optical orbiter, and I recall seeing the slow drift with respect to the background on a program that used chroma key to overlay some performers over a separate background. During the scene, the cameras were apparently locked down, but of course the two orbiters were not synchronized. If the performers were moving throughout the scene, you could not notice it, but as there was stationary foreground content, it was noticeable. The TK-41 orbiters were much slower than the example you posted, and I believe were 1 rpm as stated in the catalog.

https://www.americanradiohistory.com...on-Cameras.pdf

[nasadowsk]

Were there other cameras that used a more hyperactive orbiter, maybe? I know nothing about the history of IO cameras and orbiters...

Still a neat clip...

[old_tv_nut]

Originally Posted by nasadowsk

Were there other cameras that used a more hyperactive orbiter, maybe? I know nothing about the history of IO cameras and orbiters...

Still a neat clip...

I don't know either, but as manufacturers say, "Specifications subject to change without notice."

[Adlershof]

Originally Posted by old_tv_nut

Regarding depth of field, I can testify from personal experience with the early HD cameras that accurate focus on a 7 inch viewfinder was nearly impossible.

Similar experiences here in Germany. Suddenly "focus on the eyes" was relevant to TV studio production and frequently it could be seen, for those looking closely, how operators had to struggle on air until they got it.

Originally Posted by old_tv_nut

Cinematographers, however [...]

"For a long time, it's been common for camera crew used to drama, commercials and features to take a slightly superior attitude to people who work in live television." ...
https://www.redsharknews.com/product...e-jedi-knights


And thank you also for your notes about IO colour cameras, they explained some observations I already made. Is it a correct impression that for these productions it was a strict rule to avoid any haloing, thus any lights and reflections in the picture?

[old_tv_nut]

Originally Posted by Adlershof

And thank you also for your notes about IO colour cameras, they explained some observations I already made. Is it a correct impression that for these productions it was a strict rule to avoid any haloing, thus any lights and reflections in the picture?

There was never enough headroom above "flat white," even with the special IOs, to avoid halos on jewelry and brass musical instruments. The main goal was to avoid colored halos from bright colored clothing, like bright red dresses.

There is even an internal CBS memo I have seen noting this problem with red clothing in the field sequential color system. I can't recall if it was posted on Videokarma somewhere.