D800 remote control with HDMI output

jlittlejlittle Posts: 6Member
edited April 2013 in D6x0/D7x0/D8x0
Hi,

I'm trying to control my D800 with Nikon Control Pro 2 while at the same time have the raw HDMI feed connected into an external monitor. I can get the HDMI feed perfectly fine when the USB is not connected and I press the liveview button. When the usb is connected the HDMI feed is disconnected. Im I missing something parameter wise?

Thanks

Comments

  • paulrpaulr Posts: 1,176Member
    I don't believe you can use them both together, It does not work on a D3x so seems it's one or the other
    Camera, Lens and Tripod and a few other Bits
  • MsmotoMsmoto Posts: 5,396Moderator
    I have a vague memory of this coming up before, but cannot find it. My memory suggests that for reasons I so not understand, the USB port when connected disables the HDMI output.

    I think the reasoning is that one can use the USB output to see everything on the computer and there is no need for an additional monitor.
    Msmoto, mod
  • jlittlejlittle Posts: 6Member
    edited April 2013
    Can I grab raw video over USB without having to use the HDMI port?
    Post edited by jlittle on
  • MsmotoMsmoto Posts: 5,396Moderator
    I think video is in H.264/MPEG-4 Advanced Video Coding and as far as I know shooting RAW video is not possible. A one minute video in RAW would be nearly 74 GB of data. I think this is why video is compressed.
    Msmoto, mod
  • jlittlejlittle Posts: 6Member
    Yes, I guess not raw video. What Im trying to do is control the camera remotely by placing it in liveview then recording the video feed from the HDMI port. Its a shame that Nikon had to disable the HDMI port when a USB connection is established.
  • AdeAde Posts: 1,071Member
    edited April 2013
    In motion video lingo there is a difference between "uncompressed" and "RAW". One can have a non-RAW video feed that's still uncompressed. It is similar to using uncompressed TIFF vs compressed JPEG in stills.

    A video signal is often expressed in terms of a luma / luminance channel (brightness) plus two chroma channels (color differences). A video system might sample this signal in specific ratios, such as 4:2:2, which means the brightness channel is sampled twice as often than each of the two chroma channels.

    When using the HDMI output, the entire 4:2:2 signal sample is retained. So it is "uncompressed" since we don't lose any color information. The signal is not "RAW" since the sensor data has been demosaiced, downsized to 1080p, gamma applied, color balanced, etc. The signal has also been processed into a particular codec. But it is still considered "uncompressed".

    In comparison, when saving to the internal CF or SD card, the 4:2:2 signal is immediately compressed into a 4:2:0 signal -- meaning, the color data has been reduced by half.

    This process is called "chroma sub-sampling" and is somewhat analogous to using more aggressive JPG quality settings in stills.
    Post edited by Ade on
  • MsmotoMsmoto Posts: 5,396Moderator
    @Ade

    Thank you
    Msmoto, mod
  • IronheartIronheart Posts: 3,017Moderator
    @jlittle, what are you connecting the USB to? Are you running camera control?
  • jlittlejlittle Posts: 6Member
    USB is connected to PC
    I'm currently using gphoto2 but I have tried with Camera Control Pro 2 as well. As soon as the USB cable is connected (to remotely control camera) the HDMI feed is disabled. For example, I have place the D800 into liveview mode manually and the HDMI feed it directed out to an external monitor. As soon as I plug in the USB cable the camera goes out of liveview mode and the HDMI feed is disconnected. Not sure if theres a work around?
  • IronheartIronheart Posts: 3,017Moderator
    According to the manual, you are supposed to turn the camera off before connecting/disconnecting either the HDMI or USB cables. Have you tried connecting both cables while the camera is off and powering up and then initiating live view?
  • jlittlejlittle Posts: 6Member
    I have tried powering it on with both ports connected. The camera goes into liveview fine, but there is no hdmi signal.
  • mklmkl Posts: 1Member
    grr same thing for me its a shame......when you connect an usb on the d6OO you hav no liveview on it and no liveview by hdmi....
    so i cant connect my computer and i cant connect my remote controler focus etc etc...you find a solution??
  • IronheartIronheart Posts: 3,017Moderator
    @mkl, this is a different problem than @jlittle is experiencing, which is that LiveView works, but no HDMI output. Have you tried initiating LiveView after plugging in the USB cable? Is your camera turned off when making the connection?
  • jlittlejlittle Posts: 6Member
    I have talked with Nikon and is seems like its an internal electronic shutoff. When a +5V line on the USB input is sensed the HDMI feed is shutoff. I have not found away around this.

  • gordolakegordolake Posts: 1Member
    edited January 2014
    Hi, has anyone tried hacking this by disabling the +5V line in the USB cable ? Its not really required as its not charging the camera battery.

    D800
    ninja -2 HDMI
    dslrdashboard router USB
    Post edited by gordolake on
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