Re: Cannot select 1920x1080 (interlaced) @50Hz outside of Media Ce

Previously you stated that no rate was listed in Media Center at 1080i and
that you only assumed it was @50hz.
Its still a question of misunderstanding, this time of the notation being
used. Simply selecting 1080i in PAL mode is all that is required to get the
correct display output.

1080i in PAL mode only displays 50 half frames (fields) per second, which is
equivelent to 25 full frames per second. It's not different from standard
definition PAL TV (576i) in that way. Typically when Interlaced resolutions
are quoted with a rate number it is the field rate, not the frame rate or AC
line frequency that is meant, so 1080i50 means 1080 interlaced lines @50
fields (=1/2 frames) per second. OTOH progressive scan resolutions like
720p50 or 1080p60 do mean frame rates of 50fps or 60fps.

ATI's own notation for HDTV resolution settings, from their Catalyst Help:

a.. 720p60- Use this format for displaying 720p HDTV content broadcasted
in traditional NTSC countries (North America and Japan).
b.. 1080i30-Use this format for displaying 1080i HDTV content broadcasted
in traditional NTSC countries (North America and Japan).
c.. 1080p60-Use this format for displaying 1080p HDTV content broadcasted
in traditional NTSC countries (North America and Japan).
d.. 720p50-Use this format for displaying 720p HDTV content broadcasted in
traditional PAL and SECAM countries (Europe, Australia, most of Asia, Africa
and South America).
e.. 1080i25-Use this format for displaying 1080i HDTV content broadcasted
in traditional PAL and SECAM countries (Europe, Australia, most of Asia,
Africa and South America).

There's a pretty good description of interlaced resolutions here:

http://en.wikipedia.org/wiki/Interlace

And the PAL specification here:

http://en.wikipedia.org/wiki/PAL


"Gareth D. Phillips" <GarethDPhillips@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message news:858B6B70-33EA-4F45-AEE9-FC6196A18772@xxxxxxxxxxxxxxxx
Thanks, I appreciate your help and I think you have clarified a lot.
However
despite kind of understanding what you are saying, I AM able to select
1080i
@ 50 inside media centre (but not outside it) - this is definitley
interlaced also - not P. I definitley cannot display 1080p

"RalfG" wrote:

I think it's a case of misunderstanding how display resolution works and
confusing refresh rate/line frequency with framerates. 1080i25 is the
actual
PAL display rate for 1080i HDTV resolution, there is no 1080i50 AFAIK.
All
the values for PAL and NTSC (etc) are dictated by the specifications for
each mode. The video driver takes care of it all so you needn't be
concerned
about those details as long as you can pick the display resolution you
need
within the PAL format.

1080i resoluton is an "interlaced" display mode while 720p resolution is
"progressive" scan mode. Progressive scan is what a typical computer
monitor
uses, scanning every line sequentially, ie. @50hz for PAL, 60hz for
NTSC.
At interlaced resolutions like 1080i only every other line is scanned, so
each half screen is displayed alternately, at 25hz for PAL and 30hz for
NTSC. To the eye it appears as if the full screen is being displayed at
nearly 50hz or 60hz. Your display would need to be "1080p" capable to
work
at the 50hz setting.

The ATI Catalyst Control Center has the neccessary region settings for TV
plus additional display settings for HDTV resolutions. You are able to
force
HDTV resolutions that aren't detected automatically but it isn't
advisable
to choose a resolution setting that your display isn't capable of .. such
as
1080p50 when its maximum resolution is 1080i25.



"Gareth D. Phillips" <GarethDPhillips@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in
message news:62A47645-DF6F-4C18-A772-386CFD27B1DF@xxxxxxxxxxxxxxxx
Hi. I am really struggling to find a solution to a problem as I dont
know
if
it is an OS issue, or a driver issue but I am leaning toward OS... Any
help
would be very much appreciated.

I have a fairly new ATI Radeon 2400Pro graphics card in my Vista 32-bit
Ultimate machine. I chose this card as it is apparntly good for H.264
playback etc. I have a 37" 1080i LCD TV which is connected to the card
using
DVI - HDMI (DVI on the card, HDMI on the TV)

The best resolution the screen supports is 1080i (1920x1080) so I am
making
the assumption that HD video and Blu-Ray / HD-DVD is going to look best
in
this res (also the BBC broadcast in 1080i on the BBC HD channel in the
UK)

50Hz is very important in the UK as without running @ 50hz video on
live
TV
or DVD etc is very glitchy. Here lies my problem:

Within Media Cente if I try to select 1920x1080i @50Hz I CAN as long as
I
select "Select All Modes" and then scroll to the end of the list. The
INFO
feature on my TV confrims that the res is indeed 1080i (it doesnt
confirm
the
refresh rate but the smoothness of video suggests that the signal is
indeed
50hz)

The problem is there is no way I can select 50hz outside of Media
Centre.
In
the display properties in control pannel if I select "list all modes"
there
are only options for 25 and 30hz if I recall. No 50hz and no 60hz. I
can
run
in 1080i @30hz but video is not smooth at all. Instead I am forced to
run
in
720p@50Hz. As soon as I open Media Centre the refresh goes back to my
desired
1080i @50hz.

Can anybody suggest why the 50hz option is unavailable for 1080i? I
have
tried the Catalyst control centre and even within this app there is no
way
of
forcing this res. I am using the latest version of the card drivers
(7.10).

The card can surely do 1080i @50 as this is what Media Centre is set
at! ?

Thanks in anticipation.





.

Relevant Pages

  • Re: still no way to do custom aspect ratios?
    ... The good news is that you have found a way to display 4:3 material in normal mode. ... The video that Media ... the PHYSICAL aspect ratio of the television. ... desktop resolution and thinks the resolution in the matching aspect ...
    (microsoft.public.windows.mediacenter)
  • Re: Optimum Display Resolution (to CRT Television over S-Video)
    ... What is the best display resolution setting for the CRT ... currently the graphics card for this display is configured ... But while Linux would perhaps be able to handle things in a bit more graceful way, the Windows drivers almost certainly won't let you get down to any dirty details like that. ...
    (uk.tech.digital-tv)
  • Re: still no way to do custom aspect ratios?
    ... I am glad to hear that you found a method of forcing Media Center to fully display the 4:3 aspect ratio 1024x768 resolution video you are sending it without distortion by centering it and adding side bars after apparently down scaling it to 768x768 to compensate for the rectangular pixels which are 33% wider then they are tall. ...
    (microsoft.public.windows.mediacenter)
  • Re: Any motherboard with onboard DVI video?
    ... PCI Express display card since his video needs are very basic (no ... I very hurriedly went BACK to my VGA connector for the ... when running at native 1680x1050 resolution on the VGA connector. ...
    (alt.comp.hardware.pc-homebuilt)
  • Re: Cannot select 1920x1080 (interlaced) @50Hz outside of Media Ce
    ... PAL display rate for 1080i HDTV resolution, ... I chose this card as it is apparntly good for H.264 ... The problem is there is no way I can select 50hz outside of Media Centre. ...
    (microsoft.public.windows.mediacenter)
Loading