Welcome to InspirePilots.com

Join the leading DJI Inspire community for free!

Can someone tell me what is wrong with my video?

Discussion in 'Inspire 1 Help' started by @HDFlyover, Oct 6, 2015.

  1. @HDFlyover

    Joined:
    Oct 6, 2015
    Messages:
    4
    Likes Received:
    1
    So to start - please ignore the music, my friend who's cottage we were staying at requested it.

    There is wobble/flashing (sorry not sure of the term) between 1:10 and 1:45 on the mid to lower half of the clip, with a really noticeable event at 1:26.



    Filmed in 1080p30fps. All of my videos have this no matter how I'm flying. Can someone take me to school?
     
  2. The Editor

    The Editor Moderator
    Staff Member

    Joined:
    Aug 7, 2013
    Messages:
    6,724
    Likes Received:
    3,880
    What you are experiencing is Rolling Shutter/Jello effect.
    Are you using ND filters?
    Are your props balanced?
    Is there excessive free play on the T-Joints on the arms of the Inspire?
     
  3. @HDFlyover

    Joined:
    Oct 6, 2015
    Messages:
    4
    Likes Received:
    1
    Thanks for the insight. I didn't use a ND filter.

    I will check the props and T-Joints when I get back home later this week.

    If there is free play on the T-Joints, I'm assuming that is fixable, yes?
     
  4. The Editor

    The Editor Moderator
    Staff Member

    Joined:
    Aug 7, 2013
    Messages:
    6,724
    Likes Received:
    3,880
    Ummmmm...yes but it means dismantling the T-Connectors and adding some shims. You must then disconnect the landing gear guides and ensure there is no binding in the rotation of the motor arms.
    As long as they turn freely you can reconnect the landing gear arms and you are good to go.
    If you do not feel comfortable performing surgery like this on your Inspire you will need to send it in and have DJI fit shims to the arms.
     
  5. @HDFlyover

    Joined:
    Oct 6, 2015
    Messages:
    4
    Likes Received:
    1
    Ugh! Thank you for sharing your wisdom!
     
    AndrewH likes this.
  6. The Editor

    The Editor Moderator
    Staff Member

    Joined:
    Aug 7, 2013
    Messages:
    6,724
    Likes Received:
    3,880
    You're welcome - I would go the ND and balance props route first and retry since they are the least invasive.
     
  7. steelkite

    Joined:
    Apr 7, 2015
    Messages:
    94
    Likes Received:
    27
    The 'jello' if present, will most likely become apparent when climbing, as is the case here.
    After using filters and balancing props .. slow your accent, then change the timing in post if you need to speed it up in the video.
     
  8. InterMurph

    Joined:
    Jul 6, 2014
    Messages:
    537
    Likes Received:
    228
    I think the event at 1:26 is due to isolated aircraft vibration; the kind I see when a strong gust of wind hits the craft. ND filters aren't going to solve that problem.
     
  9. Danj503

    Joined:
    Jun 28, 2015
    Messages:
    17
    Likes Received:
    7
    What's most important to understand and what hasn't been mentioned what it is that the ND filter accomplishes for you. The only reason a ND filter works to relieve jello is because without one, and in sunny conditions, the ample light causes your auto exposure to increase the shutter speed. This captures more micro movements in each of the 30 frames per second. Your frame rate has a hand in this as well because if you film at 60fps, the shutter needs to fire at twice this value to get crisp motion. So (ideally) when filming at 24fps, your shutter can slow to 1/50th of a second and result in the least amount of jello. This slowing of the shutter smooths out those micro motions by NOT capturing them in such a short period of time (1/60 -1/200 or more) My guess is you were filming at 30 fps, but a shutter of 1/120 or more. that is too fast for that frame rate and motion wobble will be present. Hope this helps explain how shutter speed causes jello. Furthermore All the ND really does is cause your cameras auto exposure to slow down the shutter speed resulting in smoother motion. You can manually slow the shutter to relieve jello, and then use the ND for it's true purpose: to bring in the blue sky and level off exposure differences in the scene. (bright sky, dark ground). Hope this helps!
     
  10. Danj503

    Joined:
    Jun 28, 2015
    Messages:
    17
    Likes Received:
    7
    As a photographer first, and drone pilot second, I can't overstate the importance of shutter lock. I always fly with manual settings and only use auto exposure only for shots whose movement will travel through a heavy exposure change. (like from inside to outside for example). I always start with my shutter locked to 2 times my frame rate. so 24fps gets 1/48-1/50, 30fps gets 1/60, and 60fps gets 1/120 shutter. I don't go higher as this results in jello. Then I adjust my ISO to get my exposure correct never going over 800 if possible. Too noisy and shots are unusable. If you have to go higher to get correct exposure, you're no longer filming your just documenting. Also, I always expose for highlights first and if the shadows end up too dark, chances are there is still detail to work with in post, but if you have blown out highlights, you can't recover those in post so I give highlights priority. I check exposure and using manual controls I lock it before each shot, as each shot requires an adjustment. I use filters (ND and UV) when in harsh sun or hazy conditions. I also recommend a low contrast, low saturation, and minor sharpness color profile to record in. (I think it's called 'log'). This gives you the most detail in shadows, and the most latitude in post to add sharpness, contrast and color to your liking. TV's and monitors have their own added levels of contrast,sharpness, and saturation. You don't want those cranked before sending it to a TV that will crank it even more ;) Hope this helps anyone reading!

    -Dan