Progressive scan confusion - info needed

[mhjo]

I have connected a Sony DVP-NS730P (DVD) to a Panasonic Px60 via component cable. The Sony DVD has a button for "Progressive auto/cinema/video on".

What does the "Progressive auto/cinema/video on" button do? When should I use it, and why. (I can't see any difference when turning on/off).

I have been told that the Panny automatically does deinterlaceing of interlaced signals.

Can someone "enlighten" me?

tks

[Liam @ Prog AV]

With Progressive Scan on, the DVD player is deinterlacing the image. With progressive off the DVD player is sending the still interlaced image to the plasma, and the plasma is deinterlacing. What you are seeing is two deinterlacing chips (one in the DVD, one in the plasma) that are both about as good as each other!!!

[mhjo]

Thakks. But what's the use of using component cable + using prog scan player when the Plasma can do the job after beeing fed s-video or RGB signals from a standard DVD player?

[Liam @ Prog AV]

S-Video isn't as good as component or RGB, so if you use that approach then you suffer on account of a worse signal type.

RGB and component are roughly the same quality, so with a player with equally good RGB and YUV outputs, and using the plasma deinterlacing, the result will be similar whether you use RGB or YUV.

However in many cases one is better implemented than the other, or in many cases the progressive scan in the DVD player is actually better than the plasma in which case you have to use a component cable.

To be honest I reckon with progressive scan ON you will be getting less artefacts and a bit more detail, but it takes longer testing than just flicking the button over to really notice it. In fact I'm pretty sure the Panasonic has poor/no cadence detection for 2:2 where the Sony does, so you should see quite a noticeable difference in sharpness (if the plasma isn't so badly setup that other artefacts are getting in the way e.g. sharpness control....).

[mhjo]

Thanks for clearifying this for me. However, I am not sure I know what this really is:

"Panasonic has poor/no cadence detection for 2:2 where the Sony does,"
Can you explain this ?

2. I have ordered the new 42-PHD9 due in sep. I have seen all the 3:2 pulldown functions etc. Do you know what 3:2 pulldown means?

PS: Thanks a lot!

[Liam @ Prog AV]

http://www.progressive-av.com/access...nterlacing.htm

It's for film mode material only. 2:2 is the ability for a processor to identify a 2:2 field pattern, and accurately weave the two fields back together to regenerate the original full progressive frame. This pattern is used on 50Hz material i.e. PAL

3:2 pull down is the ability to do this for NTSC material where things are even more complicated (as if they weren't already!). Most displays have 3:2 because of NTSC's dominance in the market, but few have decent 2:2 (even though it would appear to be the easier thing to implement!). 2:2 is more relevant for us as it is for PAL material which is what all R2 DVDs are recorded in.

[mhjo]

Ok, maybe I am a bit nitty-grity now, but:

Q1. Why isn't the original film material transferred to mpeg as progressive material, (and leave the DVD player to do interlacing when nescessary) ?

Q2: How does the Plasma know it is receiving progressive/interlaced signals?


Q3. Why have they put deinterlacing function in both ends of the signal (dvd AND TV)?

Q4: What is the use if sending a progressive signal from a DVD player, when all (?) receiving units that can receive such signal all have buildt-in deinterlacing-function?

Q5: How is the TH-PHD8/9 deinterlacing compared to Sony 730?

[Liam @ Prog AV]

Q1. Why isn't the original film material transferred to mpeg as progressive material, (and leave the DVD player to do interlacing when nescessary) ?

Dunno. But that's the way it is. Interlacing is a 2:1 compression though so it's probably for bandwidth/file size reasons.

Q2: How does the Plasma know it is receiving progressive/interlaced signals?

THe 2:2/3:2 pulldown bit is the technique it uses to try detect if it is interlaced film mode.

Many processors use flags embedded in the signal to work out if it film mode or not (rather than try to count and compare the frames themselves).

I think a processor would usually work on the basis that if a film cadence cannot be identified (there are more than just 2:2/3:2....) then video mode deinterlacing is used.

If the signal is already progressive in the first place the processor knows this from the scan rate of the signal I think.

Q3. Why have they put deinterlacing function in both ends of the signal (dvd AND TV)?

Didn't used to, but some DVD manfacturers use it as a selling point and on poorer displays it will make a difference hence people bought them for the improvement. It's the same as these upscaling DVD players with 720p/1080i output. Bloody useless in my opinion, unless you have an exactly 720p resolution display. Otherwise you have the player giving you 720p, and the plasma still having to scale to 768p!!!

Q4: What is the use if sending a progressive signal from a DVD player, when all (?) receiving units that can receive such signal all have buildt-in deinterlacing-function?

Because the deinterlacing isn't as black and white as being done or not being done. Some deinterlacers are simply better than others, so if you have a poor deinterlacer in the plasma then you will need a better one in the DVD player (or even a dedicated video processor) in order to improve your image.

Q5: How is the TH-PHD8/9 deinterlacing compared to Sony 730?

Dunno. You've got the two items needed to compare, you tell me!!!!!

[mhjo]

I am very impressed by the answers you have givn to this subject.

I took a closer look on your commercial web site, and noticed the items you have displayed. Anything there you would recommend (in he lower price range) that can give value-for-money enhancements with my gear?

[Liam @ Prog AV]

Originally Posted by mhjo

I am very impressed by the answers you have givn to this subject.

I took a closer look on your commercial web site, and noticed the items you have displayed. Anything there you would recommend (in he lower price range) that can give value-for-money enhancements with my gear?

Ooh watch it cos once I start I'm rarely able to stop myself!!!

What you're hankering after is a dedicated video processor. Best value for money award definitely goes to Lumagen for all the adjustment tools and filters you get, plus HDTV processing, as well as leading SD film processing. These will give you the best deinterlacing (for all your sources, Sky, DVD, HDTV etc) and also the scaling. We can hook up running at 720p into a PX60 and you will see quite some improvement, although the real benefit will be seen when you get into your PHD8/9 which is better than the PX60 anyway, but also has the benefit of being driven at native resolution by the processor. This means the processor will drive the plasma at exactly 1024x768 resolution, which as good as bypasses all the inferior electronics in both your screen and DVD player and lets the better technology in the Lumagen do the work.

The result - a gobsmackingly good picture that is just so clean of artefact and error you almost won't believe it. It's subtle though, most don't notice at first because there just isn't really that much on the screen (apart from a completely clean image). But, when you flick back to without the processor and are looking at artifical sharpness (edge enhancement), mosquito noise (the weird opaque border around football players), colour shift and a general all-round fuzziness to the image you wonder why so much of the image is lost through bad processing and how you've never noticed it before!!!

[mhjo]

Thanks again. Yes, I took a very close look. I take the point. However, my wife will not... (Hard enough getting a plasma in the living-room..)

However, I thought maybe I could compomise a little. While waiting for Blu Ray, I wonder if I could achieve anything by getting a Panasonic DVD-S52 in replacement for my Sony DVP-NS730p ? (HDMI and modest upscaling....?)
+ saving the expensive component-cable and terminal board.

- Or maybe you have some better suggestions?

[Liam @ Prog AV]

Having not seen a Panasonic S52 I can't really comment but I doubt it will give you that much of an improvement. Be nice to have HDMI I guess