Creative Communities of the World Forums

The peer to peer support community for media production professionals.

Forums AJA Video Systems HD in an SD sequence trouble Kona LHe

  • HD in an SD sequence trouble Kona LHe

  • Ben Kalb

    August 31, 2009 at 3:40 pm

    I just installed FCP 7 and have a AJA Kona LHe with the newest drivers. I shot HD footage in both 720P60 and 1080i60 with my JVC HM-700 camera.

    I’m trying to place my HD footage in an SD sequence. Everything looks fine in FCP , but on my NTSC monitor the video is very aliased and shaky. I’ve rendered the sequence entirely, and video does not look this way with other regular SD material. On the computer display, the video looks good.

    Surprisingly, the 1080i60 footage looks much worse. I’ve tried changing field dominance, but with no luck. I expected the conversion to be very clean, especially because my frame rates match.

    Any ideas where I should start? Anyone else have similar problems?

  • Fred Jodry

    September 1, 2009 at 2:45 pm

    Ben, the video to your NTSC monitor is in analog, is your 1080i too? Try running the output through a VTR or digital VTR to use it`s low pass filtering as a test. Maybe, “Wait, it gets worse”. Could it be a mismatch from your JVC? At least you aren`t running across choppy audio edits and vertical (horizontal chops) in the video and it`s edits so it`s not a frame rate or typical “low horsepower” problem. Try looking at the horizontal synch pulse going to the NTSC on an oscilloscope in the line. If the JVC or 1080i monitor uses analog, test with the oscilloscope in line there too. an open ground return on the synch cable either between the camera and the Kona, or between the output and the monitor is plainly possible. Composite (vertical and horizontal combined) synch signals can go defective too.

    HD in an SD sequence trouble Kona LHe
    by Ben Kalb on Aug 31, 2009 at 11:40:47 am

    I just installed FCP 7 and have a AJA Kona LHe with the newest drivers. I shot HD footage in both 720P60 and 1080i60 with my JVC HM-700 camera.

    I’m trying to place my HD footage in an SD sequence. Everything looks fine in FCP , but on my NTSC monitor the video is very aliased and shaky. I’ve rendered the sequence entirely, and video does not look this way with other regular SD material. On the computer display, the video looks good.

    Surprisingly, the 1080i60 footage looks much worse. I’ve tried changing field dominance, but with no luck. I expected the conversion to be very clean, especially because my frame rates match.

    Any ideas where I should start? Anyone else have similar problems?

  • walter biscardi

    September 1, 2009 at 3:19 pm

    [Ben Kalb] “I’m trying to place my HD footage in an SD sequence. Everything looks fine in FCP , but on my NTSC monitor the video is very aliased and shaky. I’ve rendered the sequence entirely, and video does not look this way with other regular SD material. On the computer display, the video looks good. “

    Ok, HD is Upper Field First and your SD is Lower Field First. So your interlacing has been reversed, thus the poor quality SD.

    [Ben Kalb] “Surprisingly, the 1080i60 footage looks much worse”

    Not surprisingly, this is your interlaced native footage, so it will look worse than the 720p material.

    Why are you editing in an SD timeline? Do you need your final output to be SD? If so, edit in an HD timeline and do the downconvert with the Kona to SD.

    Walter Biscardi, Jr.
    Editor, Colorist, Director, Writer, Consultant, Author.
    Credits include multiple Emmy, Telly, Aurora and Peabody Awards.
    Owner, Biscardi Creative Media featuring HD Post

    Biscardi Creative Media

    Creative Cow Forum Host:
    Apple Final Cut Pro, Apple Motion, Apple Color, AJA Kona, Business & Marketing, Maxx Digital.

    Read my Blog!

    Twitter!

Viewing 1 - 3 of 3 posts

Log in to reply.

We use anonymous cookies to give you the best experience we can.
Our Privacy policy | GDPR Policy