205-Lines?

[dominicbeesley]

PAL gets around this by alternating the phase at line rate (simplification here) so a +10° error becomes a -10° error on the next line.Nothing is done about this and it is presented to the CRT (or whatever) as is. The eye and brain integrates this and we get the impression of the correct colour.

That's only true on "peoples PAL" (i.e. cheapo PAL), on PAL de-luxe (used on nearly all sets) a delay line is used to do the averaging and so the effect on a correctly adjusted set - instead of alernating hues is instead a slight de-saturation (which can be corrected by adjusting the colour control). [On certain early Sony sets the delay line is used differently, in effect putting PAL back to NTSC and then decoding NTSC/625. This to get round paying royalties to Telefunken etc, I had one of those sets as a kid and you had to adjust the Hue control every ten minutes until it was fully warmed up!]

The good thing about both NTSC, PAL and SECAM is that they can be applied to almost any of the black and white standards so long as you can find a handy spot to put in the colour burst...

Going back on topic, I'm following all these threads with interest, as I'm interested in collecting all these standards together for inclusion in my encoding software...it would be nice if we could collect the together somewhere (possibly on a Wiki?). It can be quite difficult researching these as there is little solid information on the net and much is in German/French/Dutch etc.

I'd be happy to look at setting up a Wiki somewhere if others are interested in submitting data...Or is there already a collection that I've missed?

Dom

[Steve Anderson]

....That's only true on "peoples PAL" (i.e. cheapo PAL)....Dom

True, but it outlined the fundamental difference without going too deep. And to a degree it's academic with the close-down of the analogue system in Europe and in the UK (one day).

Here, would you believe, they're just installing a UHF analogue PAL network shifting the seven terrestrial channels out of VHF...It appears that the powers-to-be don't realize it's 2009! But then again I suppose that's understandable as here it's the year 2552 BE....which kinda makes it less of an excuse! (We never had a Y2k problem here). Perhaps they're buying the old European transmitters which have now been freed up.

Several of those channels still use analogue PAL in the studios with baseband separate audio. Very 1972. Recently I was asked where to get a GVG300 vision mixer which hasn't been in production for some 20 years!

Steve A.

[dominicbeesley]

Sorry Steve, wasn't trying to teach granny to suck eggs! Its just that I've often spoken to people from NTSC land who think that all PAL tellys must show nasty hanover blinds! Mustn't give the wrong impression!...also I'm about half way through reading Carnt & Townsend on 405/NTSC...far more exciting than Sebastian Faulks' effort at James Bond that I've just finished!

Given the number of people I've helped who have bought HDTV boxes and tellys and then connected them together using cheap and nasty SCART connectors that are only wired for composite....I'd say baseband PAL and NTSC will last a good long while. Sad thing is they rarely spot the difference once you plug it all in properly and they actually get HD!

Dom

[Klaas Robers]

As far as I know simple PAL has never been used, as the production of the "mean colour" by the eye was wishful thinking. It doesn't work and the "venetian blinds" are very annoying, even if the colour difference is slight. And the production of the glass delay line became much easier than expected in the beginning. I have seen quite some different principles, getting cheaper and cheaper during time.

I know about the first Sony small colour TV that went around the PAL patents. It had indeed Never Twice the Same Colour. We had one in the Philips Nat.Lab. colour TV studio in ..... 1972 (?).

[Steve Anderson]

Sorry Steve, wasn't trying to teach granny to suck eggs Dom

...and I didn't take it that way, don't worry. I was just outlining the difference in the encoding, how it is decoded in the receiver can be done in several ways the way I put forward is the simplest i.e. cheapest as you say.

When PAL or NTSC was still in use in TV studios the decoding was done digitally in the studio monitor, clever sod whoever designed a digital comb-filter! These monitors were made by Barco, Sony and Ikigami to name a few...and they cost thousands of dollars each, but they were good.

Now they use glorified domestic wide-screen TVs or computer displays with a box upstream that takes several inputs and displays them as a mosaic on the screen...shame about the colour accuracy.

Steve A.

[asiekierka]

Hi.

One of you was asking about the "Television under the Swastika" documentary, right? Well, it's on Google Video somewhere. It should be.[/u]