And now for an answer from someone who makes TV programmes and films for a living and has to deal with all this HD garbage on a daily basis...
HD Ready actually means nothing in terms of picture quality. A TV that is marketed as HD Ready only has to be capable of receiving an HD signal, it does not have to be capable of displaying an HD image. They can have a downconverter built into them that converts HD into PAL, show PAL on the screen and still be called HD Ready. Many people have been conned by that and many people will continue to be because hardly anyone will actually be able to see the differece between a good PAL picture and a poor HD one (720I 422 HD, which is what is actually transmitted over the air as an HD signal, is about 6% mathematically improved over analogue PAL).
The difference between progressive and interlaced will probably mean nothing to you but I'll explain anyhow. An interlaced picture scans the odd numbered lines of a frame and calls them field A, then scans the even numbered lines of the same frame and calls them field B. The frame consists of both fields overlayed on each other. This is how you can show a 25 FPS image on a 50 Hz powered TV without horrendous flicker problems. Progressive scans the whole image, top to bottom and calls the whole thing a frame. It's a dodgy system that creates terrible motion blur in fast moving objects (especially vertical movement) but is part of how you make video look a bit more like film. Unless you use a CMOS camera because CMOS doesn't scan line after line but most cameras in the world use CCDs because they are cheaper. I can only think of one camera using a CMOS chip, the Arriflex D 20. Progressive monitors are for showing things that have been shot in progressive scan, interlaced monitors are for showing stuff that has been shot interlaced. It's that simple. The two sytems look very wrong shown on the wrong monitor. Generally a monitor capable of showing progressive can switch itself back to interlaced mode if it needs to but an interlaced monitor can't deal with progressive at all and it will get very jittery with fast moving images.
Oh yeah, and you can squeeze an HD signal onto a scart cable if it's the right type, there is more than one sort. The problem is that no TVs are wired for it. Some Scarts are built with 6 seperate Co-Ax cores and they would carry HD. HD is a big klunky signal that needs a lot of room and to be honest I'm amazed it works down an HDMI because the cores in that stuff are tiny. We have to use 2 seperate 9mm 75 ohm co-ax cables with solid dialetric to carry one picture signal, nothing else will work properly for any distance. Then again you never deal with the sort of HD at home that we deal with at work. There are many, many different HD standards.
None of you have a top of the line HD monitor by the way. At work we use 24" CRT monitors (nobody really likes to use a flat monitor, you can't rely on the output) that cost £35,000 each and weigh a ton and there are only a handful in the country. If you think that a computer monitor is better than these you're kidding yourself.
Edited by Dan, 26 March 2008 - 04:42 AM.