[mythtvnz] 50Hz vs 60Hz refresh rate

[Mark van Dijk]

This is in response to a few messages in the last couple of days about the refresh rate of the TV.  In the info below, note that i have an HDMI connection from a GT220 (VDAPU) to a 1080p LCD panel.

I have used the INFO button on my TV remote which verifies that my MythBox is connected at 1080p at 60Hz.  I have a very new TV and a new GT220 graphics card (only had it about 2 months), and ever since 
i installed them, I have been fairly dissapointed with noticable judder during screen pans.  I have always just thought that this unavoidable...

After seeing the messages about potential issues while trying to display FreeviewHD (50i) on a 60p TV connection, i have done a couple of experiments.  I went into the MythTv frontend - 
Utilities/Setup - Setup - Appearance.  In the "Video Mode Appearance" I have manually selected "Different Modes for GUI and TV Playback", and specified both the GUI and TV playback to be 1920x1080 
with a refresh rate of "any".


When i try to play back FreeviewHD content, there is a visible screen mode change on my TV - clearly indicating that the TV mode is now 1080p at 50.

Results are that the judder is greatly reduced!!!!  This is fantastic!!   I have flipped back and forth between the two different settings (60p and 50p) and FreeviewHD content is absolutly better with 
the refresh rate of "any".  Judder is *substantially* reduced.  It is not completely eliminated, but it's a lot better.  If I enable "motion flow" on my TV, then there is no perceptable judder at all, 
however this also introduces an unacceptable "daytime soap" feel to movies which i can't stand (see one of my previous posts), so I'm going to keep motion flow disabled.


A previous poster mentioned that this "euro judder" when displaying FreeviewHD at 60Hz was likely to be 5Hz, and just from my experiments, this appears to be correct.



-- 

Mark van Dijk