Question about prog scan and LCD projectors

Vladman

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Hi all,

Ok, before I go into details, I'll ask a very simple question:

Do ALL LCD projector support progressive scan input signal?

I had so far assumed so, but it looks like I'm wrong... :(

Thanks,

Vlad.
 
You seem to have answered your own question :confused:, as you say not all projectors accept PS, some do on some inputs and not others. What was it that prompted you to ask?
 
Not all can recieve a prog scan signal.

However all projectors must convert the signal into progressive scan (if it isn't done so already) so technically speaking the picture will always be "progressive" whether the DVD player does the conversion or whether it happens inside the projector. Usually the projectors internal conversion is pants, hence DVD players that do it themselves!!
 
KraGorn, thanks for a quick reply.

Well... <big sigh>

As briefly as possible (because if I go into detail, it will be a very long post):

I have a Philips Bsure SV1 LCD projector.

I have just bought the much-praised Panasonic E65 dvd-recorder, to replace my ageing (but excellent) Toshiba SD-200E dvd player.

One of the features I was looking forward to was the Panasonic's ability to output progressive scan. And, as mentioned in my previous post, it never occurred to me to question my projector's ability to accept progressive scan signal, as it accepts component input (that's how I had my Toshiba connected to it) and in all I ever read on this subject, I never came across anything to suggest otherwise (that not ALL LCD projectors support progressive scan signal).

But when I connected the E65 last night (component to projector), and all excited went into the menu and changed progressive scan from "off" to "on", the picture instantly got scrambled, it kind of vertically doubled, started jumping and shaking all over the screen… and it was insantly very obvious this was definitely NOT what progressive scan should look like. :(

I looked through all the settings, and as far as I could see, I don't have anything else set incorrectly which could cause this. The only conclusion I can come to is that my projector simply doesn't recognise the progressive scan signal. I had a look in its manual too, and there's no mention of progressive scan in there, neither that it does or that it doesn't support it. I just thought having component inputs that it would.

Will gratefuly receive any advice or opinion on this.

Thanks,

(dejected) Vlad.
 
No you wrong. It does take a progressive scan signal.

Technical specifications
LC3131 (bSure SV1)
LCD 3x 0.7" high-temperature poly-silicon active matrix LCDs
Resolution SVGA
Brightness 1200 ANSI lumens
Lamp 132W
Contrast 300:1
Average lamp lifetime 6000 hours
Fan noise 27 dB

Lens F/1.8 - 2.2 ; f = 28.4 - 34 mm; 1.2x Manual Zoom; Manual Focus
1.2x Manual Zoom; Manual Focus
Projection distance 1,1 - 10 m (image diagonal 27.5" - 250")

Input signals
Video
NTSC 3.58, 4.43 ; PAL B,G,D,H,I,N,M ; SECAM
S-video/S-VHS (Y/C)
Component video input RGB-Y,YCbCr,YPbPr (480p,720p, 1080i)
Computer
Computer
PC and MAC compatible, Multi scan VGA-SXGA
Horizontal scan rate: 15 - 108 kHz
Vertical refresh rate: 50 - 120 Hz
Bandwidth: 140 MHz

Compatibility Microsoft® Windows® 95/98/ME/2000/XP compatible

Input connectors
Video
Component in R/Pr/Cr,G/Y,B/Pb/Cb (3x RCA)
1x S-Video (Y/C DIN)
1x CVBS Video (RCA)
Computer
1x Data in (15p D-sub)
 
That spec looks like NTSC progressive (480p) is supported but not PAL progressive (576p).

All is not lost; the effect PS would have on your image may well not be that great. The PJ itself will create progressive scan from any input anyway. It's just a matter of how good a job it does.

You may be able to try this out if you have or can get an NTSC disc. If the specs quoted are right then this PJ does support NTSC progressive, so by comparing NTSC interlaced with NTSC progressive, you should get an idea of the difference (if any).
 
Aha, that might be it!

I don't know enough about this to have been able to decipher what those numbers in the specification meant (Component video input RGB-Y,YCbCr,YPbPr (480p,720p, 1080i)), but I am not at all surprised the knowledgeable folks like you here do. :)

I do have quite a few region 1 discs, so I'll try that tonight.

On that subject though now, I'm a little confused about something. Does this mean that whenever I play a region 1 disc, I'll have to change one of the settings in Connections menu (can't remember exactly what it's called) manually from PAL to NTSC, and vice versa, when playing a region 2 dvd? I never had to do this on my Toshiba, it all seemed to happen automatically...

Thanks very much for your replies guys. :thumbsup:
 
IF you find progressive is worth doing (and you may not), then I'd guess you need the DVD player to output Interlaced for PAL (576i) and progressive for NTSC (480p). I don't know whether or not you can make it do this automatically, or whether you'll need to do it manually every time you change disc format. As I say, you may find that NTSC interlaced is hardly different anyway.
 
Nigel, I presume it's just penny-pinching on the part of the DVD manufacturer which results in their supporting 'p' output for only one of the video standards and that there's no technical reason for doing this?
 
KraGorn said:
Nigel, I presume it's just penny-pinching on the part of the DVD manufacturer which results in their supporting 'p' output for only one of the video standards and that there's no technical reason for doing this?
Pal progressive (576p) has only officially been recognised as a DVD standard for about 18 months - maybe 2 years.

It's possible that the PJ in question is pre official pal progressive days...?
 
You'll find it's the other way round, not so long ago (when progressive scan was pretty much what upscaling is nowadays - i.e. confusing, rare, expensive, not necessarily better) only NTSC could be done in prog scan. IIRC PAL Prog scan didn't get on too well with macrovision, or stripped out copy protection or something. So PAL Prog scan was rare as rocking horse doo doo and no display manufacturer ever bothered to consider it as a possible signal that would need decoding in the same way NTSC Prog Scan would. The result is a whole bunch of projectors and plasmas which either do not work with prog scan at all, or only accept NTSC variants of it!!
 
You might be able to force your DVD player to only push out a NTSC progressive scan image irrespective of what region the DVD is.
My Toshiba Sd340 has that ability. Look in the video setup menu of your DVD player.
 
Liam @ Prog AV said:
You'll find it's the other way round, not so long ago (when progressive scan was pretty much what upscaling is nowadays - i.e. confusing, rare, expensive, not necessarily better) only NTSC could be done in prog scan. IIRC PAL Prog scan didn't get on too well with macrovision, or stripped out copy protection or something. So PAL Prog scan was rare as rocking horse doo doo and no display manufacturer ever bothered to consider it as a possible signal that would need decoding in the same way NTSC Prog Scan would. The result is a whole bunch of projectors and plasmas which either do not work with prog scan at all, or only accept NTSC variants of it!!
Now now Stewie...eat your sprinkles...!!

:D
 
Wow, I'm impressed!

What "educated banter"! Things look progressively clearer ;) now.

I'll try it tonight and report my findings. Thanks a bunch guys.
 
Hey, something just occurred to me.

If 480p stands for progressive NTSC signal, and 576i stands for PAL interlaced, how come that number (576 with either an "i" or a "p") doesn't feature in my projector's spec at all? Because I obviously can see interlaced PAL, but seem to be having problems with progressive...

Ok, just nit-picking now...
 
That is exactly the point Vlad!!! Your PJ does not list 576p as compatible which is why your DVD players 576p output (aka PAL Prog Scan) does not work. 576i is listed since you can see the interlaced PAL signal. Confusing innit!!!!
 
No, Liam, what I was saying and what IS confusing is that neither 576i nor 576p are listed! :confused:
 
Aaah I see what you mean :oops:
 
cyberheater said:
You might be able to force your DVD player to only push out a NTSC progressive scan image irrespective of what region the DVD is.
I suspect (without being able to confirm) that converting the line structure of the image from 576 to 480 will degrade it, more than feeding the PJ with progressive will enhance it. I'd guess therefore that this option is to be avoided.
Vladman said:
...what IS confusing is that neither 576i nor 576p are listed! :confused:
480i - which is interlaced (non-progressive) NTSC - isn't listed either. Maybe these specs only list the "oddball" signal types. In other words, because it can do NTSC and PAL via composite or SVideo, then it follows, it must be able to handle 480i and 576i. Whereas 480p, 720p and 1080i are never carried using composite or Svideo - in other words they might be termed "non standard signal types". Perhaps that explains the contents of the list.
KraGorn said:
Nigel, I presume it's just penny-pinching on the part of the DVD manufacturer which results in their supporting 'p' output for only one of the video standards and that there's no technical reason for doing this?
In this case it's the projector that doesn't support 576p. And, as discussed, it's most likely because its origins predate 576p as a signal type in widespread use.
 
Right, tried it last night.

It didn't work! :( Changed the setting to NTSC, turned progressive scan on - the same thing! Totally garbled screen. Took me ages to figure out how to recover the normal picture. The manual says hold stop and time slip on the "main unit". Well, there isn't a time slip button on the main unit or I'm blind! I did try time slip on the remote and stop on the main unit but that didn't seem to work either... Managed to somehow get the picture back in the end...

Why on earth isn't it working in NTSC progressive scan, when my projector is supposed to support that?? I really didn't want start entertaining this thought, but is it possible my E65 is faulty? Or it could be the projector...? Arrgh...
 
Got the quote site already!! I have a bookmark folder called "Quotes" which lists all the good Simpsons, Futurama, Family Guy, King of the Hill etc quote sites. Sad, but true (I'm on a lot of forums with a lot of different sigs!)

Vladman - what did you turn onto NTSC? The only thing that your DVD should be able to do is in default mode, when playing an NTSC disc, be able to send an NTSC progressive scan signal when Prog Scan is activated. If you're projector is funny with this signal then you may need to switch inputs back and forth (to allow the PJ to resync to the new frequency) or you may need to "tell" the projector in the setup menu (not by shouting at it!!!) that it is recieving a prog scan signal.
 
Your DVD player may have an option like PAL/NTSC/Auto. It should be set to auto.

To see what happens with an NTSC signal, you need an NTSC disc. A PAL disc (even if the player is set to NTSC) won't generate a 480p signal. Only an NTSC disc will.

So - try this and then try interlaced vs. progressive.
 
Liam, if I remember correctly, there's a setting simply called "TV setting", which only offers choice of either PAL or NTSC (no Auto). I changed that to NTSC.

LV, by an NTSC disc, you mean region 1 disc?

But the problem is that the Functions menu on the E65 only works in stop mode, not during disc playback. And the prog. scan option is in that menu, so I can only turn it on or off when not playing a disc. The moment I switch it to on, the screen goes, so I can't try playing a disc, and then try switching prog. scan on and off during the playback. Hang on... Now there's a thought... Maybe I should press play regardless of the screen going funny after switching prog. scan on... Maybe the singal needs to reset or something...

What do you mean by:
If you're projector is funny with this signal then you may need to switch inputs back and forth (to allow the PJ to resync to the new frequency)
Do you actually mean I need to unplug the physical connectors and plug them back in? Back and forth? I'm confused. :confused:

With regards to the settings on the projector side, there's nothing there with which I could "tell it" what kind of signal to expect.
 

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