7 Replies Latest reply: May 4, 2010 7:06 AM by capaho
DJH2007 Level 1 Level 1 (10 points)
I currently play movies in HD purchased over Apple TV iTunes and played from Apple TV via component cable to my Panasonic Viera 42" plasma.

Its an enjoyable experience except I do notice telecine judder whenever there are long slow panns within the movie.

I'm vaguely familiar with the concept that this is due to 3:4 pull down where every 12th frame is played twice as it converts the original 24fps into something that my home setup plays - probably 50hz or 25hz or something.

Question - is this limited by my TV or by the AppleTV itself? Ie. Could I eliminate this by buying a new top spec TV that is capable of recieving and playing 24fps or will I be wasting my money as the AppleTV is already juddering?

Many thanks,
Dan.

iPhone 3G 16GB (3.1) / iMac 2.8ghz 3GB/ MBP 13" 2009, Mac OS X (10.6), 2xAE(g) 1xAE(n) 1xAEBS (new dual band)
  • Matt Larson2 Level 1 Level 1 (80 points)
    Are the files you are playing back clean 24 fps files where each frame in Quicktime appears to be a complete frame and none are redundant?

    I playback 24p files on my Apple TVs all the time and don't have any issues. I am in the NTSC world though (29.97 fps).
  • Roidy Level 1 Level 1 (35 points)
    DJH2007 wrote:
    Question - is this limited by my TV or by the AppleTV itself? Ie. Could I eliminate this by buying a new top spec TV that is capable of recieving and playing 24fps or will I be wasting my money as the AppleTV is already juddering?

    Many thanks,
    Dan.


    Don't buy a TV with 24Hz playback just for the AppleTV, as the AppleTV is only capable of outputting 50Hz or 60Hz anyway. Have you tried setting your AppleTV's resolution to a different resolution/refreshrate? I have my AppleTV set to '1080p HD' which is a 60Hz resolution and my content plays back perfectly however if I set it to '1080p HD - 50Hz' then I get the same judder you describe.
  • Winston Churchill Level 10 Level 10 (88,830 points)
    As you are in London you will probably have your video output set at 50 Hz, try changing it to 60 Hz for these movies, you will need to change it back for 25 fps content or you may see the same thing.

    The tv does make a difference, we have one tv from five that has this issue, we only need change the one tv in this way.
  • DJH2007 Level 1 Level 1 (10 points)
    Thanks.
    So does the AppleTV iTunes store have movies at both 24fps and 25fps then?

    I did indeed have my output set to 720p - 50hz. I've switched it to 720p HD and tested it on the 2012 trailer and it seems to have eliminated the telecine judder (although it was only slight anyway so difficult to find test material)

    ps. My ATV only goes up to 1080i and not the 1080p mentioned here? Is that an upgrade or a region thing?
  • Winston Churchill Level 10 Level 10 (88,830 points)
    I haven't seen any movies in anything other than 24 fps, TV shows & podcasts can be 24, 25 or 30, if you don't have a lot of home movies in your itunes library or use the tv for playback of recorded tv broadcasts (eyeTV) then it might be worth keeping the setting at 60 Hz and occasionally either adjusting for or putting up with 25 fps content.

    It may of course transpire that you don't get any judder when playing 25 fps at 60 Hz.

    When connected to the tv by HDMI, the tv will tell the tv what resolutions it can work at, the tv will then only show those options to you.
  • DJH2007 Level 1 Level 1 (10 points)
    Thanks.
    I'll test it on Heroes. Thats classed as a TV show but is HD and has many slow panning shots of the scenery / cityscape.
  • capaho Level 4 Level 4 (3,650 points)
    When connected to the @tv by HDMI, the tv will tell the @tv what resolutions it can work at, the @tv will then only show those options to you.


    My ATV shows 1080i as an option for my TV, but I get no video from the ATV if I select that option.