Smartphones, Neutral Density Filters & Motion Blur

Discussion in 'Movi Technical' started by Rorick Edge, Oct 19, 2018.

  1. Rorick Edge

    Rorick Edge Active Member

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    This post arises from thinking about the various discussions on loading up a smartphone with a filter adapter and neutral density filters and trying to balance the resulting device, which, to make my personal view clear, reminds me of a Rube Goldberg contraption :)

    This is liable to be controversial, but here goes anyway...

    I think that an awful lot of the smartphone video that I see on YouTube would not benefit from a fixed shutter speed and therefore not from the use of neutral density filters. Take the example of 24fps and 1/48th of a second. At that frame rate, the purpose of 1/48th of a second is to emulate traditional motion blur.

    Motion blur only matters if the subject (a) is moving and (b) is prominent in the frame. If the subject is stationary, or is not moving much, it doesn't matter what the shutter speed is because there's no motion blur to be had. To take a simple example, if the shot is of an urban or rural landscape, I don't think that it matters a wit what the shutter speed is. Also, due to the widespread use of wide angle lenses, a high percentage of the time the subject is not sufficiently prominent in the frame that traditional motion blur will even be visible, certainly not at the size and resolutions at which smartphone videos are typically viewed.

    I also think that when a specific shutter speed is desired, changing the ISO (within reason), or indeed shooting in more favourable light, is a hell of a lot easier than messing with a filter adapter and filters and trying to balance the result.

    Just as an exercise, it's interesting to watch a few smartphone videos with this in mind and think about what shots actually benefit from locking the shutter speed at 1/50 of a second (for 24/25 fps) or 1/120 of a second (for the now fashionable 60 fps).

    All of that said, I'm quite interested in reading other views on this issue.
     
    #1 Rorick Edge, Oct 19, 2018
    Last edited: Oct 19, 2018
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  2. Simon Hughes

    Simon Hughes Member

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    I'm in agreement with you, Rorick, certainly for the material I tend to shoot such as mostly locked-down shots for landscape/cityscape and with wide lenses. It's not as if we are shooting with extremely fast glass for a shallow DOF and extreme bokeh effects. If I can get away without strapping anything on the front of my 8+ with Moment wide (and hopefully soon, the anamorphic), I'm happiest.
     
  3. John Chu

    John Chu Active Member

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    Here is something I got a couple months ago and it works fine. It is really light, so balancing your iPhone shouldn't be an issue with the Movi. It clips right on.

    http://a.co/d/icrGgfJ

    Although I've definitely forgotten that I have it in my bag.
     
    #3 John Chu, Oct 20, 2018
    Last edited: Oct 20, 2018
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  4. Rorick Edge

    Rorick Edge Active Member

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    John shoots on New York streets a few times a week and uploads his videos, which also reflect his interest in binaural sound, to this YouTube channel: https://www.youtube.com/user/chung123video

    A few days ago, he uploaded a video shot with the new Moment anamorphic lens. I stand to be corrected, but I rather doubt that he is also using a 66mm Moment filter adapter and a 66mm neutral density filter, and when I watch his videos I don't find myself saying "Horror, the motion blur is all wrong".

    To put this in perspective, I use the Movi with a Sony RX0, which is a bit smaller than a GoPro. With the Sony, one uses filters with a face plate replacement that adds no weight to the camera, plus 30.5mm/1.2" filters. I have no problem balancing the Sony, and it's easy to use filters with it, but I don't go looking for reasons to haul them out.

    On a smartphone, the Moment system, which I mention because it seems to be favoured here, adds not just a lens, but also a 66mm/2.6" adapter and a 66mm/2.6" filter, all of it forward of the camera's native lens. The photo below, from Moment's web site, shows the result. No wonder there's a whole thread about trying to balance this.

    The question is, what is being gained :)

    moment-hoya-daytrip-8.jpg
     
    #4 Rorick Edge, Oct 20, 2018
    Last edited: Oct 20, 2018
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  5. Simon Hughes

    Simon Hughes Member

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    The Moment filter adapter is actually for 62mm filters, not 66mm.
     
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  6. John Chu

    John Chu Active Member

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    I read a tip a couple years back by Philip Bloom about adding-faking blur to strobey looking footage by duplicating the clip, stacking it above the original clip and sliding it over it one frame.

    Then add some blur to the top clip and adjusting blend modes.

    I never did get it looking right--- but think a software solution would be useful.
     
  7. Rorick Edge

    Rorick Edge Active Member

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    Hey John,

    I have an impertinent question that I've wanted to ask for a long time. I just watched your latest upload:



    The storage implications are huge if you are keeping everything that you upload in a week. Do you see this as a Garry Winogrand approach to video? Or is there a plan?

    Obviously, it's none of my business, but I can't resist asking. What do you plan to do, if you're willing to talk about it, with all this footage?

    Cheers
     
  8. John Chu

    John Chu Active Member

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    That's the dilemma with digital storage: what to keep. But storage is relatively cheap? So keep almost everything?

    I store the projects and files on bare 3.5" 7200 1TB hard drives after deleting temporary render files. (Don't ask me about longevity or backup on those drives--- I have no idea what the future holds or whether or not those files will be readable.)

    I can get a 1 TB drive for around $30-40 at Microcenter.

    Once I fill up a project drive. I pull it from my computer and put in a fresh drive. I also use a bare drive dock if I need to retrieve or shuttle stuff around.

    I also have a shoebox worth of MiniDV and Digital 8 cassettes and then I also think about Swedish Death Cleaning.
     
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