-icon flares - in colo(u)r

[J. P. Gilliver]

(Sorry, I can never remember whether it's plumbicon or vidicon that
exhibit these.)

I normally associate these flares (if flare is the right word, as at
their best/worst they're black!) with monochrome images, but there's an
early colour version in

from about 5:45 to about 6:20, on Ms. MacLaine's sparkly dress.

[NY]

Post by J. P. Gilliver
(Sorry, I can never remember whether it's plumbicon or vidicon that
exhibit these.)
I normally associate these flares (if flare is the right word, as at their
best/worst they're black!) with monochrome images, but there's an early
colour version in http://youtu.be/37WvidrBvOI from about
5:45 to about 6:20, on Ms. MacLaine's sparkly dress.

Interesting. If you'd not said that it was video, I'd have said that this
looks as if it had been shot on film.

It's image orthicons that exhibit flare (white highlights turning black at
the centre, or black patches in sea of white getting a white centre).

Plumbicons show coloured smear on movement of white highlights: candle
flames, or reflections of studio lights or sun on windows, shiny foreheads
etc. In bad cases, the image "sticks" on the picture for a few seconds (or
more) - especially noticeable on early ENG (electronic news gathering)
reports where a photographer facing the camera fires a flashgun and you get
a little purple/magenta rectangle which fades gradually.

Vidicons are the spawn of the devil (!). They show smear on everything (not
just overexposed highlights) as if several frames had been averaged
together. That's why they were only used for security cameras and early
domestic video cameras.

[charles]

Post by NY

Post by J. P. Gilliver
(Sorry, I can never remember whether it's plumbicon or vidicon that
exhibit these.)
I normally associate these flares (if flare is the right word, as at
their best/worst they're black!) with monochrome images, but there's
an early colour version in
http://youtu.be/37WvidrBvOI from about 5:45 to about
6:20, on Ms. MacLaine's sparkly dress.

Interesting. If you'd not said that it was video, I'd have said that this
looks as if it had been shot on film.
It's image orthicons that exhibit flare (white highlights turning black
at the centre, or black patches in sea of white getting a white centre).
Plumbicons show coloured smear on movement of white highlights: candle
flames, or reflections of studio lights or sun on windows, shiny
foreheads etc. In bad cases, the image "sticks" on the picture for a few
seconds (or more) - especially noticeable on early ENG (electronic news
gathering) reports where a photographer facing the camera fires a
flashgun and you get a little purple/magenta rectangle which fades
gradually.
Vidicons are the spawn of the devil (!). They show smear on everything
(not just overexposed highlights) as if several frames had been averaged
together. That's why they were only used for security cameras and early
domestic video cameras.

Vidicons were used in broadcast cameras. The Plumbicon (a Phillips trade
name) came later.

[NY]

Post by charles

Post by NY
Vidicons are the spawn of the devil (!). They show smear on everything
(not just overexposed highlights) as if several frames had been averaged
together. That's why they were only used for security cameras and early
domestic video cameras.

Vidicons were used in broadcast cameras. The Plumbicon (a Phillips trade
name) came later.

Ah, I was never sure whether vidicons were ever used in broadcast cameras. I
thought that the first broadcast-quality cameras after the image orthicon
were plumbicon and saticon. Evidently I'm wrong.

I hadn't realised just how insensitive (in terms of effective ASA number)
vidicon-type cameras were:
https://en.wikipedia.org/wiki/Video_camera_tube#Vidicon says that the
Saticon was about 64 ASA which is fine for outdoors but needs very bright
lighting to allow a small aperture if a significant depth of field was
needed for artistic reasons.
http://www.earlytelevision.org/pdf/rca_tv_eye_instructions.pdf gives the
speed for a vidicon as 50 ASA, for a monochrome camera, so a colour camera
with its losses in the coloured filters and the prisms would be a lot less.


Compare that with
https://juser.fz-juelich.de/record/830330/files/J%C3%BCl_0467-PP_Hopmann.pdf
which says that the speed of an image orthicon was around 10,000 ASA ;-)
https://frank.pocnet.net/sheets/180/5/5820A.pdf gives 8,000 ASA, so a
similar figure.



The "don't point the camera at a bright light" restriction for tube cameras
must have been a real problem - and the absence of it for solid-state
cameras must have been very welcome. I was in the audience at a recording of
the Royal Institute Christmas Lectures in about 1980. They used several
full-size pedestal-mounted cameras and a hand-held camera for close-ups or
for low-angle shots. In one lecture the floor manager had to stop recording
for a couple of minutes because the cameraman for the hand-held camera had
caught a studio light in vision and evidently he decided that the
after-image was severe enough that it wouldn't fade in time for when his
camera was next used in the shooting script. They must have had spare camera
warmed up and running, because they brought in a spare, swapped the cables,
and had it running commendably quickly.

[J. P. Gilliver]

Post by NY

Post by J. P. Gilliver
(Sorry, I can never remember whether it's plumbicon or vidicon that
exhibit these.)
I normally associate these flares (if flare is the right word, as at
their best/worst they're black!) with monochrome images, but there's
an early colour version in
http://youtu.be/37WvidrBvOI from about 5:45 to about
6:20, on Ms. MacLaine's sparkly dress.

Interesting. If you'd not said that it was video, I'd have said that
this looks as if it had been shot on film.

Ah, maybe it was (1965 I think); I just was _reminded_ of the orthicon
flares.

Post by NY
It's image orthicons that exhibit flare (white highlights turning black
at the centre, or black patches in sea of white getting a white
centre).
Plumbicons show coloured smear on movement of white highlights: candle
flames, or reflections of studio lights or sun on windows, shiny
foreheads etc. In bad cases, the image "sticks" on the picture for a
few seconds (or more) - especially noticeable on early ENG (electronic
news gathering) reports where a photographer facing the camera fires a
flashgun and you get a little purple/magenta rectangle which fades
gradually.

I remember those.

Post by NY
Vidicons are the spawn of the devil (!). They show smear on everything
(not just overexposed highlights) as if several frames had been
averaged together. That's why they were only used for security cameras
and early domestic video cameras.

I remember being told - don't think I ever saw it - that there's a bit
of material from one of the Apollo missions on the moon, where the
astronaut accidentally caught a bit of the sun, and you could see a bit
of the tube target burn off and roll away. Don't know what sort of tube
they used there (IIRR much slower frame rate [and lower resolution?],
and sometimes sequential colour).

Wandering more off topic (for the thread, not the 'group): I've often
wondered what was used for the original Yuri Gagarin video; it was
certainly discernible pixels, so I assume not a tube as such at all.

[Roderick Stewart]

On Wed, 21 Jun 2023 14:51:35 +0100, "J. P. Gilliver"

Post by J. P. Gilliver
I remember being told - don't think I ever saw it - that there's a bit
of material from one of the Apollo missions on the moon, where the
astronaut accidentally caught a bit of the sun, and you could see a bit
of the tube target burn off and roll away. Don't know what sort of tube
they used there (IIRR much slower frame rate [and lower resolution?],
and sometimes sequential colour).

That was Apollo 12 as I recall. Apollo 11 was the first one to land on
the Moon, but only had a monochrome camera (slow scan, optically
converted for broadcast) so Apollo 12 was going to show the first
colour pictures from the Moon, but didn't because they accidentally
pointed it at the Sun and burnt half the target. I was working in TC7
at the time and all of us engineers realised instantly what had
happened because at the time it was deeply ingrained in us that
pointing cameras at bright lights was the one thing you should never
do with them, though the pundits in the studio waffled on for ages
about some technical problem or other they clearly hadn't a clue
about. They kept speculating that maybe the NASA engineers would be
able to fix the problem, whatever it was, though we knew there was no
chance at all. Modern chip cameras like the ones in phones don't seem
to have this weakness, but with any sort of tube camera you had to be
really careful, always parking cameras tilted slightly down or capping
the lens if they were not going to be used for a while.

The Moon camera would have had fairly serious automatic exposure and
automatic gain systems because the astronauts had enough to do and
couldn't have been expected to control these things, and I don't think
it had a viewfinder anyway. (That would have required a CRT, so too
expensive on weight and power). The part of the target that had been
burnt by the Sun became peak white, causing the AGC to try to correct
it so the other half of the picture became black. It was frustrating
to think that if there had been a way of adjusting the electronics we
might at least have had half a picture from the part of the target
that was working, which would have been better than nothing.

Apollo 13 had what with glorious understatement was described as "a
problem" and didn't get to land on the Moon, so the first colour
pictures from the surface were from Apollo 14.

Rod.

[Mark Carver]

Post by Roderick Stewart
at the time and all of us engineers realised instantly what had
happened because at the time it was deeply ingrained in us that
pointing cameras at bright lights was the one thing you should never
do with them, though the pundits in the studio waffled on for ages
about some technical problem or other they clearly hadn't a clue
about. They kept speculating that maybe the NASA engineers would be
able to fix the problem, whatever it was, though we knew there was no
chance at all.

Nothing has changed in 50 years then, and funny how the producer didn't
think to seek the opinion of the studio's technical staff !

[Roderick Stewart]

On Thu, 22 Jun 2023 14:54:57 +0100, Mark Carver

Post by Mark Carver

Post by Roderick Stewart
at the time and all of us engineers realised instantly what had
happened because at the time it was deeply ingrained in us that
pointing cameras at bright lights was the one thing you should never
do with them, though the pundits in the studio waffled on for ages
about some technical problem or other they clearly hadn't a clue
about. They kept speculating that maybe the NASA engineers would be
able to fix the problem, whatever it was, though we knew there was no
chance at all.

Nothing has changed in 50 years then, and funny how the producer didn't
think to seek the opinion of the studio's technical staff !

Allowing technical staff to make a contribution to the artistic
content of a programme would have been a big breach of protocol, as it
would make such staff entitled to demand payment along the same lines
as the 'talent' who are paid to offer opinions, however uninformed
they might be.

I suspect the same sort of thing might be happening right now with
most of the coverage of that submarine. I don't waste my time watching
any broadcast stuff now, just the short clips that end up on Youtube,
and there's been nothing yet that tells us anything new. From what
I've seen, the most realistic estimate of the probability of ever
finding out what happened to it looks like absolute zero, but they've
got to fill their screen time with something, so they'll all be hoping
for a miracle, which of course won't happen.

Rod.

[John Williamson]

Post by Roderick Stewart
I suspect the same sort of thing might be happening right now with
most of the coverage of that submarine. I don't waste my time watching
any broadcast stuff now, just the short clips that end up on Youtube,
and there's been nothing yet that tells us anything new. From what
I've seen, the most realistic estimate of the probability of ever
finding out what happened to it looks like absolute zero, but they've
got to fill their screen time with something, so they'll all be hoping
for a miracle, which of course won't happen.
Rod.

The company have now announced that it appears to have imploded, as they
have found debris which could only have been the result of such an event.

[Roderick Stewart]

On Thu, 22 Jun 2023 20:53:52 +0100, John Williamson

Post by John Williamson

Post by Roderick Stewart
I suspect the same sort of thing might be happening right now with
most of the coverage of that submarine. I don't waste my time watching
any broadcast stuff now, just the short clips that end up on Youtube,
and there's been nothing yet that tells us anything new. From what
I've seen, the most realistic estimate of the probability of ever
finding out what happened to it looks like absolute zero, but they've
got to fill their screen time with something, so they'll all be hoping
for a miracle, which of course won't happen.
Rod.

The company have now announced that it appears to have imploded, as they
have found debris which could only have been the result of such an event.

Yes, within minutes of me saying we would never know what happened. At
least we know, even if it's not the miracle we would have liked.

Rod.

[Brian Gaff]

I know what you mean though, my old Hitachi colour camera did this on very
sparkly bright things like glitter balls and some see scenes, but it was
more often than not blue or yellow. I don't know hat tube it had in it, it
was too early for ccd.

Brian
--
Brian Gaff - ***@blueyonder.co.uk

Blind user, so no pictures please!

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Post by J. P. Gilliver
(Sorry, I can never remember whether it's plumbicon or vidicon that
exhibit these.)
I normally associate these flares (if flare is the right word, as at their
best/worst they're black!) with monochrome images, but there's an early
colour version in http://youtu.be/37WvidrBvOI from about
5:45 to about 6:20, on Ms. MacLaine's sparkly dress.
--
The first banjo solo I played was actually just a series of mistakes. In fact
it was all the mistakes I knew at the time. - Tim Dowling, RT2015/6/20-26

[NY]

Post by Brian Gaff
I know what you mean though, my old Hitachi colour camera did this on
very sparkly bright things like glitter balls and some sea scenes, but
it was more often than not blue or yellow. I don't know what tube it had
in it, it was too early for ccd.

CCD and other solid-state sensors had peculiarities of their own.
Highlights sometimes produced a vertical line across the whole picture,
as if a maxed-out pixel triggered all the others in the same column to
mis-read. I've not seen that for a number of years, either on dedicated
camcorders or on mobile phone cameras in video mode, so evidently the
technology has improved.

[Brian Gaff]

Just asked my friend who now has the camera, he says its vidicon tubes. No
wonder it was big and awkward. Indoors though with normal lighting it looked
fine.
Brian
--
Brian Gaff - ***@blueyonder.co.uk

Blind user, so no pictures please!

This document should only be read by those persons for whom Paranoia is
normal
and its contents are probably boring and confusing. If you receive this
e-Mail
message in error, do not notify the sender immediately, instead, print it
out and make
paper animals out of it. As the rest of this disclaimer is totally
incomprehensible, we have not bothered to attach it.

Post by NY

Post by Brian Gaff
I know what you mean though, my old Hitachi colour camera did this on
very sparkly bright things like glitter balls and some sea scenes, but it
was more often than not blue or yellow. I don't know what tube it had in
it, it was too early for ccd.

CCD and other solid-state sensors had peculiarities of their own.
Highlights sometimes produced a vertical line across the whole picture, as
if a maxed-out pixel triggered all the others in the same column to
mis-read. I've not seen that for a number of years, either on dedicated
camcorders or on mobile phone cameras in video mode, so evidently the
technology has improved.