LCD TV's - refresh rates and stuff

[Pob]

Would be interested to know what others users do about resolutions & refresh rates when it comes to the various types of media.

I have been using GBPVR with a Toshiba LCD for a while (had to get an Nvidia card to make it work).
I set the resolution manually to 1920x1080, 50Hz. It's been fine - lovely smooth ticker-tapes on the news channels, great HD...
But I did have to crank up the brightness, and fast movement not great - not judder as such, more of a shimmer around edges - and MKV files were not as smooth.
Read this:
http://www.plasmatvreviews.org.uk/articl...-scanning/ and realised that I have been using 1080i - which is fine as all TV here is interlaced.
1080p gave a brighter, sharper image - definately better for Windows programs, but TV / DVD had the judders. Then found that using the 'Set HDTV format' option to 1080p in the Nvidia drivers had set it to 60Hz. Had to manually edit the 1080p settings to get 50Hz. So now had brighter image - Windows good, DVD good, but the ticker tapes not as smooth as they were - slight judders.
Remembered that MKV files are 24fps - so tried 1080p 24Hz and although smooth video, the audio goes out of sync after a minute or so. Found that 1080p 60Hz gives best results for MKV's.

So it got me wondering how everyone else does things - do you change refresh rates, progressive / interlaced, maybe even resolution depending on media, or leave it on one setting?

So far I'm thinking;
Windows - best at 60Hz 1080p
DVD - 50Hz, OK at 1080i - looks better with PC progressive (720p or 1080p)
MKV files - 60Hz, 1080p
SD and HD TV - 1080i 50Hz - 1080p 50Hz has some advantages, some disadvantages.

[martint123]

Sorry, but I don't mess with any of that - just let the PCH take care of it
(It's the main reason I bought it...)

[pBS]

hmm,you have a 780g mb *and* a hd3450?
turn off the video detail enhancement to get rid of 'shimmering' on edges...
[of course you'll still see some on occasion, because of compression artifacts]

and the differences you're seeing are probably down to codecs used on those different files...
diff codecs deinterlace differently..so what codecs using on the file types?
the codec is responsible for deinterlacing in it's own settings, unless using full dxva, then the video card is doing it..

i only use 720p for everything on my 3450 so it's more forgiving on deinterlacing...
but all motion is smooth.. [from sd to bluray]
i don't play dl'd mkv...you never know if it's a good encode or not...results will vary...
if you didn't make it yourself, bad play doesn't necessarily mean it's your system...

typically use the highest framerate possible, this gives deinterlacers more to work with when they have to change things alot...[60 or 120hz]

you can't 'match' refresh to video always, as some mpeg is mixed framerate also..
[23.97 and 29.97 in same video] so must rely on deinterlacer, only option is to use best one...[and hope it can properly handle the many framerates possible]

best ones i've found so far for mpeg2 are ffdshow and ati avivo..cyberlink and Purevideo only if you have nvidia card..
for 264 i like mpchc video dec., but cyberlink gives best consistent results..
VC1 i like mpchc codec..nearly perfect...

[Pob]

Sorry, but I don't mess with any of that - just let the PCH take care of it
(It's the main reason I bought it...)

I don't know much about the PCH - are you saying it changes it's output refresh rates, interlacing / progressive 'on the fly'?

[Pob]

hmm,you have a 780g mb *and* a hd3450?
turn off the video detail enhancement to get rid of 'shimmering' on edges...
[of course you'll still see some on occasion, because of compression artifacts]

SNIP.

No - the PC in question is Nvidia 8800GS - I have three PC's running GBPVR now - I change things too often to keep my sig upto date!
I don't use any edge enhancements, or any configurable post-processing.
LCD's and plasma's are all progressive. If fed an interlaced signal, they must deinterlace it first. So you have a choice with interlaced content - feed it to the LCD interlaced and let it do the conversion, or let the PC convert it to progressive and the LCD display it without further processing.
I guess LCD's will vary as to how well they deinterlace, but you cannot ever get away from the fact that an interlaced signal, because the way only half the screen is drawn at a time, the effective refresh rate of the screen is halved, which can be percieved as less-fluid motion. i.e. a 50hz signal is halved because it takes two cycles to draw one frame.
Because LCD's have not-so-great response times anyway - typically 8ms compared to CRT @ 0.5ms, I think you can definately see a difference between interlaced and non-interlaced content on fast-panning shots. Anyway it's all in the eye of the beholder, but I think there is general consensus that DVD's, which are interlaced, can look better if converted to progressive by the player, and there is no question that blue-rays are true 24fps and play smoothest at 24Hz progressive- though even then LCD's vary in how they deal with 24Hz inputs - my Toshiba multiplies it by five to get 120Hz.
IMO if you leave your PC at just one output resolution / refresh rate, you cannot be doing justice to all the different media - I just wondered what other users did.
BTW I have always used the program resolution changer to change resolutions from my Hauppage remotes http://www.12noon.com/displaychanger.htm using lines like this in Iremote.ini;
GRNPOWER={run(C:\Progra~1\devnz\gbpvr\PVRX2.exe -fse)}
BLUE={run(C:reschange.exe -width=1920 -height=1080 -refresh=50)}
YELLOW={run(C:reschange.exe -width=1920 -height=1080 -refresh=24)}
GREEN={run(C:reschange.exe -width=1920 -height=1080 -refresh=25)}
RED={run(C:reschange.exe -width=1920 -height=1080 -refresh=60)}
So changing res quickly is not a problem - but the limitation is that you cannot force the output to interlaced / progressive - Nvidia drivers only 'remember' one setting for each refresh rate at any given resolution...
So at present I switch between 1080i 50Hz for TV, and 1080p 60Hz for 24fps content. As there is no way to also have 1080p 50Hz from the remote, I guess I will settle on 720p 50Hz for DVD's...

[martint123]

I don't know much about the PCH - are you saying it changes it's output refresh rates, interlacing / progressive 'on the fly'?

No, I just set its output to HDMI, 1080p 50Hz and leave it at that.
It just plays what you throw at it without having to do anything.

[Pob]

No, I just set its output to HDMI, 1080p 50Hz and leave it at that.
It just plays what you throw at it without having to do anything.

Yeah - I was / am very happy watching everything at 1080i 50Hz - but I still think you can get better results with some media by changing the output.
As stated, 1080p 50hz from my PC does give a good result for TV (i.e. letting the video card turn the 25fps interlaced TV signal into a progressive signal), but I can definately see a difference on the ticker tapes - they are not quite as smooth - but the difference is minute.

[mvallevand]

If your monitor is capable, the PCH can be configured to automatically switch from 24/50/60 fps depending on the source material.

Martin