can anything be done about tearing on an LCD Proj

Comer

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When I run my projector at any refresh rate other than 60hrz I get tearing (almost constant). Is there anything that can be done to correct this or is it just the projector?

Any ideas greatly appreciated


Conor
 
Radeon VE 32MB. I was under the impression that it was the projector that was responsible for tearing, not the PC


Conor
 
Originally posted by Comer
When I run my projector at any refresh rate other than 60hrz I get tearing (almost constant). Is there anything that can be done to correct this or is it just the projector?

Any ideas greatly appreciated


Conor

Hi Conor,

This is normal behavior for many LCD or DLP projectors, OK for NTSC but crap for PAL.
 
Originally posted by Jeff
Hi Conor,

This is normal behavior for many LCD or DLP projectors, OK for NTSC but crap for PAL.

Thanks 4 the reply Jeff but I don't understand, why is it OK for NTSC?

And surely it can't be true of all LCD/DLP projectors. I don't consider myself to have that critical an eye but if some members here are viewing their pjs at refresh rates of othr than 60Hrz and are experiencing tearig they must notice it and if so why aren't they all complaining like crazy about it on the forum?

Conor
 
60Hz is OK for NTSC because NTSC uses 60Hz (59.94xxx). I can't really say why more people don't compare about tearing, but you often here of people trying to use 72Hz on LCD and DLP projectors which is absolutely ridiculous.
 
Originally posted by ROne
I would say its projector dependent, I can't get ride of tearing in any rez or refresh rate on the VGA.

However on component in (even coming from the PC.) I get no tearing whatsoever.

Hi ROne

I do not get tearing at 640X480X60Hrz, but I do get quite jerky motion. I also get this on a CRT monitor at 60Hrz. But if I change the refresh rate to 75Hrz for Pal and 72Hrz for ntsc I get quite an improvement as regards the jerky motion but then I get tearing on the PJ regardless of resolution.

Conor
 
Originally posted by Jeff
60Hz is OK for NTSC because NTSC uses 60Hz (59.94xxx). I can't really say why more people don't compare about tearing, but you often here of people trying to use 72Hz on LCD and DLP projectors which is absolutely ridiculous.

My 'Old fashioned' Davis Cinema One DLP (SVGA 800x600) runs just fine at 72Hz or 75Hz, there is nothing ridiculous about that at all :)
At 60Hz people see the rainbows, and the colour wheel makes more noise.

It is the XGA DLP and LCD that usually suffer the tearing.

The SVGA are often OK for some reason.

Higher resolution is not always best with a fixed panel.

I am going to guess that when Jeff had a DLP it was XGA, and that Comers LCD is also XGA ?


Mark (wishing I had the space for a CRT)
 
Originally posted by Mark Grant


I am going to guess that when Jeff had a DLP it was XGA, and that Comers LCD is also XGA ?


Mark (wishing I had the space for a CRT)

Sorry Mark, bad guess mine is SVGA:p

Conor
 
Hello Comer,

What make and model is the projector?

Does it also tear with a static image, such as windows desktop, at other then 60Hz or just DVD playback?

Mark.
 
Now that Conor has shown me what tearing is..... im intrigued to this as well. We know that it happens, but why does it happen?

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Originally posted by Mark Grant
Hello Comer,

What make and model is the projector?

Does it also tear with a static image, such as windows desktop, at other then 60Hz or just DVD playback?

Mark.

I only get tearing with DVD playback. At 60Hrz it is what I call micro-tearing (new term Patent pending:D ) Lots of tiny tears at different hights up and down the image. A good place to look for it is with the Universal logo. Watch the word Universal as it turns into the image on front of the Earth. Watch the left of the letter U and if you have micro-tearing (patent pending) you will see a number of small slashes appear up and down the letter u

When I change the refresh rate the tearing is the classical slash across the image usually either one third, one half or two thirds up the screen.

Warning: if you look for this and start seeing it...:(

I agree with ROne, I recon that it's caused by the projector and I would be very surprised if there is a solution.

Sorry Buns for showing you this I hope that it isn't going to affect your viewing pleasure. BTW I got lost going home and saved about half an hour on my journey up. Either I hit a time warp bubble going home (boy if I had a penny for every time that's happened...I'd have three and a half pence) or I made a balls of navigating my journey up)


Conor
 
:D Conor!

I have now been keeping an eye out for tearing, i do see it, but to be honest most of the time i just forget about it altogether so it doesnt really affect my viewing.

I dont know if this is at all relevant, but Mark Rejhon who is working on H3D said that tearing is often a driver issue, he managed to resolve a tearing issue for someone with updated drivers.......

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Justto add tmy 2p. :),

I own a Davis DLS8 (800 x 600), and like Mark Grant, I run NTSC at 72hz and PAL at 75hz, and I don't get tearing either.

The Davis 650 is a higher resolution pj, but doesn't have triple buffering, so suffers from tearing (at frequencies other than 60hx IIRC). This is where the other Davis models have an advantage.

Many but not all pjs are designed to run at 60hz, and can't handle other refresh rates. This suits NTSC because of the (almost) 60hz refresh rates of NTSC and the encoded 3:2 pull down. PAL has the equivalent of 2:2 (with a slight speed up), so trying to fit 25 into 60 will cause stuttering pans.

Generaly it's a pj problem, but it's interesting to hear that a driver problem cured it with someone over at AVS - do you have a url for that thread?

Cheers.

Gary.
 
My next question to Comer was going to be were his drivers up to date, cos I've heard that too. Especially as it seems common to get 'tearing from a HCPC, but not from component vid' syndrone. I'd try everything on the PC before giving up and saying 'it's a projector issue'. Surely a SVGA pj displaying a 800x600 signal on VGA should't diplay tearing unless it's told to by the VGA signal, or cannot display at the refresh rate set by the VGA card, in which case you can change it. The problem must lie somewhere between the DVD software and the VGA out, the drivers would be a good place to start looking.
 
I think the reason you don't get it on component ie because it's supplying the pj with a refresh rate it's designed to get - 50 or 60hz.

With an htpc you're given it a refresh it wasn't designed for, so the image processing can't keep up. Using the htpc at a refresh rate the pj wants will work though.

Gary.
 
You'll never see tearing on a CRT projector. :p
 
I saw this one guy rip a telephone book in half on the telly once, don't try and tell me that's not tearing ok? ;)

Gary.
 
Well I downloaded the latest driver for my graphics card and of course ended up having to reformat the hard drive. It's no big deal, I can reformat and have everything back in order in one and a half to two hours, as I've done it so often.

I have only tested it on the monitor and at refresh rates of 75hrz and 100hrz I get smooth playback with no tearing on Pal material. The same is true of 72hrz for NTSC. So this proves that there is nothing wrong with the PC. However when I change the refresh rate to 60hrz the stuttering is back. For this reason I reckon that people running a PC with a fixed panel projector at 60Hrz are experiencing stuttery pictures.

I havent tried it on the pj yet but I'm sure that when I do I'll find stutter at 60hrz and smooth playback at 75/72hrz but with tearing.

Now my search begins for a projector that can run at refresh rates of other than 60hrz without tearing.

BTW is it possible to get the pj to run at 50hrz?

Conor
 
I haven't got a 50hz option in my default monitor refresh rates - anyone know of a monitor that supports 50hz as well as 60, 72 and 75?

I'd like to try 50hz just to see if it makes rainbows more visible from my DLS8.

TIA

Gary.
 
Comer,

Mine's running at 75hz, no tearing. I read my manual (shock) last night, and sure enough it says 800x600 and 1024x768 at 75hz is doable, there's a huge table of poss. resolutions, refresh rates anf horizontal freq. in the back. I'm a lucky b****** I was green as grass when I bought it, only marginal improvement since! Did you say once you had a Tosh MT, or was that someone else?

You might find 50hz hard to find in a CRT these days, people usually want the opposite from their monitor! It's a nuisance having to fiddle constantly with your settings, one of the biggest bugbears with the HCPC concept. I solved this one by not having a monitor, using s-vid out to the TV if there's some fiddling to do and a compelling reason not to use the projector. Currently, I have a dust prob, got the builders in....
 
Hi Maw

My projector is the Tosh MT3 and it is also suppossed to support a whole host of resolutions from VGA to XGA and refresh rates of 60Hrz to 85 hrz. But to say a projector supports a particular resolution and refresh rate is one thing..to say that it, like your pj, it supports without any tearing is another thing. Remember that most people using a pj with a PC would never see tearing as they are usually watching a static image. It's only with a HCPC that problems with motion manefest themselves. I called Toshiba about this last year and by soome miracle I was put in touch with a guy "whose job is not to answer customer queries" but when I had him on the phone he agred to talk to me.
I asked about the stuttery motion, the refresh rate and tearing. After about 10 seconds of silence he answered with just one word..."Pass"
I said "WHAT?"
He had absolutely no idea and had never heard of a customer complaining about this before. He then asked why would anybody want to use the pj to watch movies from a PC. That indicated to me that this conversation was going to yield absolutely nothing.

I'm convinced that alot of people have tearing and all people watching at 60hrz have stutter but they do not notice it. Last night I set up the PC after my reformat and I must admit that the new driver did reduce the stutter a little but had no affect on the tearing. I pointed out to my wife what the stutter and tearing would look like and we sat down to watch about 1 hour of Lord Of The Rings. Chapter 2, Concerning Hobbits, is a good one to watch out for stutter and tearing with so many slow pans, particularly just before Gandalf (can't spell that) gets to Bilbo's house. The cameras pans from left to right just before showing Gandalf arriving outside Bilbo's house. Anyway after the hour my wife had not noticed one instance of tearing or stutter (she also forgets a movie 5 minutes after seeing it...some people are so lucky:)). I am sure that there are lots that never see it and if they do probably think that it's aproblem with the DVD.

I was going to post a question on the pj forum asking people if they can change the refresh rate on their pjs without tearing but I'm not sure if I could really trust the results. The HS10 really gets my juices flowing but I would be very afraid of buying a pj without demoing with my PC and that is very difficult to do here in Ireland.

Conor
 
I'd always put stuttering down to the PC itself, 1st time I watched a DVD was on an old PC with a celeron333, it stutters like crazy! Fortunately it's 7 year old user never watches snow white in her bedroom, 'the screen's bigger downstairs daddy' The next computer, a 700 athlon did it much less, and the 1.3ghz doen't do it at all that I can see. Sounds like Tosh customer services are really on the ball!

Also sounds like you need a week off in England with the base unit in your luggage. I had 6 PJ's demonstrated at home with the athlon pc, and the NEC won. Definitely no tearing, not even when it's connected to my laptop, which has a 16mb SIS graphics system. Felt sick watching Dr Zhivago last night though, the camera work to blame I think, all close up fast panning.
 

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