[Bruce Abbott]

Originally Posted by Gorf

The A1000 had already the "costly" part of generating a color composite signal from RGB built in.

So it is ok to do it in one direction but not in the other?

It makes sense to produce signals in the format used by the highest bandwidth display device (ie. RGB monitor), then other (lower bandwidth) formats are not compromised by the quality of the source.

The A1000 used an MC1377, which has RGB to YUV conversion built in. This could be done relatively cheaply because the YUV signals only had to exceed the low bandwidth of its internal chroma modulator (~250kHz chroma bandwidth and 4.5MHz luma bandwidth).

Going the other way is not the same. To maintain quality going from YUV to RGB the circuit must have a much higher bandwidth than is required for composite output. This alone makes it more expensive. The other problem was the lack of demand meant no 'cheap' off-the-shelf chips were available to do the job (plenty were available that did YUV to RGB conversion, but they were optimized for use in TVs where the source was low bandwidth composite).

It also made sense for the 'standard' format to be a simple one that was easy to implement accurately. YUV is not a simple format. It has different color spaces depending on the application (NTSC, PAL, YPbPr etc.). With RGB there is no argument over whether the signal is compatible with your equipment. With YUV it's which 'YUV'?

it would make sense in a YUV configuration to have two different EHB modes:
one only affecting Y (darker shade of same colour)
one affecting U and Y (different colour of same brightness)

Two different EHB modes now? Already your idea is suffering from feature creep. But this is typical. If the average Amiga fan had been in charge of the A1000's design it never would have seen the light of day.

Flickerfixers are a terrible workaround for a shortcoming anyways, that should not have been necessary - ECS should have been out 1987 at the latest ... and should have included a line doubler.

That's easy for you to say, but producing a design that accurately promoted all existing screen modes to VGA without ballooning the cost was not easy. Commodore's first attempt failed because they couldn't get it to work.

Amber is agnostic to the colour-format anyways: it just stores 12bit values and does not care if there are RGB or YUV.

Of course Amber was 'agnostic', but it was not responsible for producing the video output. A circuit was still required to convert the digital bits to analog. If the data was stored in YUV format then that circuit would have the added burden of converting high bandwidth YUV to RGB.

"cheap cheap cheap" is what killed Commodore and the Amiga ...

No, it was what kept them going. If the Amiga had been a similar price to a PC then few people would have bought it. We know this because few people bought the more expensive models. The Amiga was never about just getting amazing hardware and software - it was about getting it cheaper. The custom chips were part of that because they integrated stuff that cost a lot to do separately. Using RGB was part of it too, because you could buy the base machine and hook it up to a TV to save money, with the option of purchasing a low cost RGB monitor to improve the picture quality when you could afford it.

What really killed Commodore was squandering development resources trying to chase the high end (with the A3000 etc.). But they had a long tradition of doing this, producing a slew of business machines you never heard of while getting most of their sales from the VIC20, C64 and A500 - all 'low-end' home computers built down to an affordable price. The key to holding onto this market is to produce a machine that has amazing capabilities for the price, and does it with the minimum amount of hardware. That means not filling it up with features of dubious advantage that only appeal to technogeeks.

But at the same time it would have been even better suited to video production as it actually was.

The video production industry was well used to paying high prices for specialist gear. For them the Amiga was an incredible bargain even without YUV (which wasn't used much). For the rest of us, having YUV instead of RGB would have just been another compatibility issue (like those parallel and serial ports on the A1000 that had the wrong gender - what were they thinking?).