Any Gopro tricks to increase dynamic range?

Discussion in 'Flight Following' started by sarangan, Oct 18, 2019.

  1. sarangan

    sarangan Line Up and Wait

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    When using a gopro mounted on the cockpit ceiling behind the pilot, the outside view always ends up saturating the video, while the cockpit panel shows up very dark. At night, I have the opposite problem. The panel saturates the camera, and the outside view is too dark. I tried making some gradient ND filters, but the improvement has been marginal. Is there any trick out there to make this work?
     
  2. Martin Pauly

    Martin Pauly Pre-takeoff checklist

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    There's nothing you can do with the camera itself. However, you can use what influence you have to reduce the enormous contrast between inside and outside. E.g. record flights on days with an overcast, not with blue skies. Or record at "night" when there's in reality still a little bit of daylight left. That's staging a scene, though, not recording on the fly - but it works.

    Tinted windows (or "Jet Shades") help a lot on bright days. They reduce the amount of light from the outside and thus make the outside more compatible with the inside.

    In editing, you cannot create more dynamic range than the camera was able to record, but you can make what little you have look a whole lot better with good color grading. I tried to explain that a while ago in this video:


    In a dark night there's not much you can do. GoPros with their tiny sensors are not good at low-light recording.

    - Martin
     
  3. James331

    James331 Ejection Handle Pulled

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    I put a rage polarized non fisheye lens on mine, pretty easy and helped a bit for cockpit as well as sUAS
     
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  4. RyanShort1

    RyanShort1 En-Route

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    If you could stand it, lighting the panel up a lot would be another way to possible affect things, kinda like using a flash in a room so the windows aren’t blown out white.
     
  5. ktup-flyer

    ktup-flyer En-Route

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    What GoPro do you have?
     
  6. Eric Stoltz

    Eric Stoltz Line Up and Wait

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    Two cameras could help. One on the needles and dials, one over the shoulder out the front.

    Also, if you're sporty with color correction, shoot in ProTune, and try to fix it in post.

    Is your computer up for the challenge? What editor are you using?
     
  7. LongRoadBob

    LongRoadBob Cleared for Takeoff

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    Seems strange that they haven’t made headway in Automatic Gain Control, software filtering for situations like this.
    I have the same problem when our band plays, people filming for us from the audience where it is dark, aim it at the stage which is lit up, and it washes out.

    I have a Zoom video/audio recorder which is made for musicians mainly for just this. It has a mode which helps even out the contrast, but in actuality, it is a slight improvement but doesn’t knock ones socks off.
     
  8. Shepherd

    Shepherd En-Route

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    Neutral density filter.
    Won't cure it, but it will help.
    I got the mount and adjustable filter from Amazon. Not expensive.
     
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  9. Mike I

    Mike I Line Up and Wait

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    ProTune, as mentioned above, is the answer. With ProTune enabled, set color to "Flat" instead of "GoPro Color". This records in a wider dynamic range gamut, and will give you greater shadow/highlight details. You'll have to punch the video in post, apply a LUT, or give it a one-light color grade, though.

    A Neutral Density filter won't affect dynamic range, as it simply darkens the entire frame equally. It will help with prop blur and could help with video vibration issues (by slowing the shutter speed of the camera).
     
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  10. Sinistar

    Sinistar En-Route

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    There's only so much range you can tease out with protune configured clips.

    There are a few ways to handle this, some already covered:

    Neutral Density lowers the entire scene, great for prop bananas. But not much help here.

    Picking a gray day or near sunset or sunrise as Marty stated is about the easiest way.

    Lighting up the panel could help. I could imagine a small LED light panel like a videographer would use. They are adjustable output and as you spend more you can control the light color. But where do you mount it.

    Back to protune/Gopro..go the opposite say and increase shutter open time (lower number) or force higher gain (oso) or just force the EV up. The panel will get lighter but the outside sky will start to blow out.

    Aim the camera up or down to have less windshield in the scene which will result in the same effect as the previous paragraph.

    Have a very dark panel. I think people with black or dark gray panel get slightly better results.

    Try a Graduated ND filter. This would be ideal. Set the dark part in the top half. But any objects (like your head or side posts) might look weird. I'm gonna try this one day since I still have an old slide on set around here someplace.
     
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  11. flyingron

    flyingron Touchdown! Greaser!

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    This.

    We use these in regular photography to keep the sky from overwhelming the terrain in landscape photos.
     
  12. sarangan

    sarangan Line Up and Wait

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    Graduated ND filters was the first thing I tried. But the results were only marginally better. Its not just the front view, but the side views also need to be attenuated. But the commercially available graduated ND filters only run in one direction. I do have access to optical coating systems, so I spent a bunch of effort to make a custom graduated ND filter that runs vertically and horizontally. It got better results, but they are still not to my satisfaction. It seems I need different gradients in the X and Y directions. All that would take a lot of trial and error, and even then it would only work for one type of camera and one type of cockpit. It would be nicer if there was an electronic solution. Attached are some snap shots of my results so far, without filter, as well as with the two kinds of filters I made.
     

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