English NTSC TV's.

[dieseljeep]

Originally Posted by wa2ise

Back in 1996 I worked for Samsung developing a multistandard decoder chip. KS0127 datasheet. If the burst changed frequency line to line, it was SECAM. If the burst frequency was steady, and line to line phase was 180 degrees flip. it had to be NTSC, if it was (something like +45 and -45 IIRC), it was PAL. And we'd switch in the appropriate processing. Our chip could handle a variant of NTSC running at 4.43MHz subcarrier, or PAL with a subcarrier at 3.58, though few if any countries broadcast those. We PLLed on the horizontal line frequency and used counters to identify the burst subcarrier frequencies.

I looked the data sheet and it's really impressive!
It took a group of highly-gifted engineers to come up with that scheme.

[NewVista]

Originally Posted by dieseljeep

I looked the data sheet and it's really impressive!
It took a group of highly-gifted engineers to come up with that scheme.

Large analog+digital jungle-chip:

Done in Silicon Valley? Even with workstation circuit development > simulation > photo layout systems, what if fabricated batch had bugs!?

After all that development, many chips soon obsolete, before R&D costs can be recovered?

[ceebee23]

Having seen PAL and NTSC in their real world forms OTA and on analogue cable...let's not over state the problems of either.

Far greater difference in quality with the two systems lies in the 525/60 625/50 standards.

From a viewer perspective .. 625 line (ie 576i) makes for a noticeably sharper image.

But I have to say my experience is that the colour via PAL is better (somehow red never looked right in NTSC) .... but the much feared phase error never occurred when viewing late NTSC OTA (80s+).. not sure if it was an issue in 50s and 60s.

Feeding my late model Sony Trinitron NTSC from tape or DVD vs same program from PAL sources subtle differences in colour and black level are noticeable... along with 24 to 30 frame motion issues on the NTSC versions.

I am not talking technically here but purely subjectively.. how it looks to me...clearly different TV sets and broadcasting quality would play a big part.

PAL sets do not have a phase control - Hue/Tint for a reason ... you simply do not see phase error even when present.

BUT none of this is fair.. what would 625 line NTSC look like or 525 line PAL? (Or for that matter SECAM)

What does 405 line NTSC /PAL look like? Anyone ever seen that? The BBC seems to have not wanted to migrate to 405 line colour using NTSC because it was too good and might have reduced the demand for the 625 line service.

Did you guys in the NTSC world with tube sets suffer phase errors when you still had analog broadcasts? Real world test ... not lab stuff.

[NewVista]

Originally Posted by ceebee23

(somehow red never looked right in NTSC) .... .

NTSC has wider red depth, so incompatible with PAL TVs

I'd forgotten that one - another reason PAL sucks.

[ppppenguin]

Originally Posted by NewVista

NTSC has wider red depth, so incompatible with PAL TVs

I'd forgotten that one - another reason PAL sucks.

The original NTSC red phosphor was indeed more red than current red phosphors. The problem was that it was also dim, something that was answered by rare earth phosphors, at the expense of colour gamut. All CRTs used since rare earth phosphors were invented (early 1960s?) don't go so far into the red.

There are no practical differences between the colour gamuts in PAL and NTSC. The colour gamut and rendering are largely down to how the cameras are set up and to a lesser extent the CRT. I've seen some really horrible CRTs but that's not a fault of the colour coding system.

As for colour gamut on LCD etc displays, this varies a lot. Sometimes good, sometimes horrible.

I agree about the difference in flicker between 50Hz and 60Hz. This is exacerbated by larger screens. Peripheral vision is much more sensitive to flicker than central vision. Overall, PAL has slightly better resolution than NTSC but in practice this is usually compromised by receiver design and CRT dot pitch. Comb filter decoders came much earlier to NTSC than PAL. A good PAL comb is more difficult. They certainly improve resolution and reduce artefacts.

Many years ago I spent a fair bit of time staring at the input and output monitors connected to a BBC "ACE" standards converter. High quality monitors, everything properly set up. It was hard to distinguish which was PAL and which was NTSC. Unless you caught the monitors out of the corner of your eye in which case the flicker gave it away.

[dtvmcdonald]

Originally Posted by ceebee23

Having seen PAL and NTSC in their real world forms OTA and on analogue cable...let's not over state the problems of either.

Far greater difference in quality with the two systems lies in the 525/60 625/50 standards.

From a viewer perspective .. 625 line (ie 576i) makes for a noticeably sharper image.
.

Did you guys in the NTSC world with tube sets suffer phase errors when you still had analog broadcasts? Real world test ... not lab stuff.

The main difference I saw in NTSC/PAL (50HZ) in old sets
(pre LCD or plasma non-sweep, light always on) was the horrendous
flicker at 50Hz, making it virtually unwatchable at respectable brightness.

I never noticed color problems with NTSC on live material. I saw
it only on material from very cheapie film chains. This dates
all the way back to 1954. I got my own set (actually a college
TV room set, but I ran it) in 1962. It never suffered color
problems after I put a locking pot on the hue control.

I have an RCA CT-100 from 1954, restored this summer. I have it actually
"calibrated" to match my modern calibrated flat screen. Colors
are not absolutely identical on all material, but are on most.
The difference could be corrected by adding two more color
adjustment pots, as it depends on 10% resistors in the color matrix,
and its so close I have not bothered. 10% error is easily visible,
my errors are in the 5-10% range
This, of course, is with modern source material. Looking at
very old prerecorded VHS tapes it looks ... excellent,
without adjustment. Just not absolutely perfect. I looked
at two 40 minute long slide shows I made of two recent vacations
I took on the CT-100 and they had perfect color.

PAL was a solution to a non-problem. The solution to the REAL
problem (50 Hz flicker) was the light-always-on LCD or plasma set.
Incidentally, phase alternation was not invented by the Germans,
but was developed in about 1951 by RCA and Hazeltine. I have
seen the "CPA" (color phase alternation) prototype (which is
PAF, phase alternating field, though RCA also tried PAL) working and
it does work OK. Nobody noticed interfield flicker.

[Colly0410]

Originally Posted by ceebee23

What does 405 line NTSC /PAL look like? Anyone ever seen that? The BBC seems to have not wanted to migrate to 405 line colour using NTSC because it was too good and might have reduced the demand for the 625 line service.

.

Read somewhere that 405 NTSC looked superb, presume this was under lab conditions though. What it would have been like on sets out in the wild with interference, ghosting, low signal level that many 405 line viewers used to put up with can only be speculated on. I'm wondering if it would have coped fairly well with it having a lower definition/bandwidth?

[old_tv_nut]

Originally Posted by Colly0410

Read somewhere that 405 NTSC looked superb, presume this was under lab conditions though. What it would have been like on sets out in the wild with interference, ghosting, low signal level that many 405 line viewers used to put up with can only be speculated on. I'm wondering if it would have coped fairly well with it having a lower definition/bandwidth?

There is a rule in video media: "Content is king." People were happy to watch terrible-quality bootleg VHS copies of Star Wars. That is not to say that improved quality has no value, but it is ancillary to the programs. So, if 625 lines was never a thing, people would have watched 405 color contentedly, I think; but having 625 available at the same time as color definitely pushed things in that direction.

[Mr Hoover]

Originally Posted by Colly0410

Read somewhere that 405 NTSC looked superb, presume this was under lab conditions though. What it would have been like on sets out in the wild with interference, ghosting, low signal level that many 405 line viewers used to put up with can only be speculated on. I'm wondering if it would have coped fairly well with it having a lower definition/bandwidth?

There's a lot of info here on the BBC R&D site, just put NTSC in as a search term.
https://www.bbc.co.uk/rd/search?query=NTSC&submit=

[old_tv_nut]

Originally Posted by Mr Hoover

There's a lot of info here on the BBC R&D site, just put NTSC in as a search term.
https://www.bbc.co.uk/rd/search?query=NTSC&submit=

Thanks for posting that. I didn't know they studied the effects on multiple existing B&W receivers. You may know that the U.S. NTSC did similar studies before adopting the standard, although there was more emphasis on the theoretical problems. Those resulted in the infamous change from 60.00 Hz scanning to (60)(1000/1001) Hz.

There were similar studies of the ATSC digital TV system effects on existing analog receivers during the transition period, mainly focussed on adjacent channel interference effects. These resulted in requiring precision offset frequencies between NTSC stations and lower adjacent ATSC stations.