In the olden days, producers knew what visual effects were. Now they’ve gotten into this methodology where they’ll hire a middleman – a visual effects supervisor, and this person works for the producing studio.
They’re middle managers. And when you go into a review with one of them, there’s this weird sort of competition that happens.

It’s a game called ‘Find What’s Wrong With This Shot’. And there’s always going to be something wrong, because everything’s subjective. And you can micromanage it down to a pixel, and that happens all the time. We’re doing it digitally, so there’s no pressure to save on film costs or whatever, so it’s not unusual to go through 500 revisions of the same shot, moving pixels around and scrutinizing this or that.

That’s not how you manage artists. You encourage artists, and then you’ll get – you know – art.

If your idea of managing artists is just pointing out what’s wrong and making them fix it over and over again, you end up with artists who just stand around asking “OK lady, where do you want this sofa? You want it over there? No? Fine. You want it over there? I don’t give a fuck. I’ll put it wherever you want it.” It’s creative mismanagement, it’s part of the whole corporate modality. The fish stinks from the head on down. Back on Star Wars, Robocop, we never thought about what was wrong with a shot.

We just thought about how to make it better.

Phil Tippett

3D camera tracking in Fusion or other

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silean483
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3D camera tracking in Fusion or other

Post #1 by silean483 » Tue Oct 10, 2017 10:51 pm

Hey folks, I hope you are all well.

This is a question for folks who are familiar with 3D camera tracking. Assuming someone has a Panasonic GH4 with the speedbooster adapter enabling the sensor to get close to Super 35 from Micro Four Thirds, my question is, if footage is shot with that camera with the adapter mounted, have you ever experienced difficulty in tracking the shot and solving the camera? I am asking this because to me, the adapter might mess with the camera data in terms of calculating an accurate focal length in the 3D tracking software. Have you ever had any issues with that particular camera and adapter? I assume the solve with be more accurate if footage was shot on that GH4 without the adapter.

Your thoughts?

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Re: 3D camera tracking in Fusion or other

Post #2 by ShadowMaker SdR » Wed Oct 11, 2017 12:23 am

I don't know about this combination specifically, but camera trackers will work with what they're given. Effectively as long as the angle of view turns out correct, the matching of the actual focal length is less important for the end result. (that's why forced perspective tricks work in-camera). The biggest problem for camera matching GH4 shots will most likely be the inherent rolling shutter TBH.

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Re: 3D camera tracking in Fusion or other

Post #3 by SirEdric » Wed Oct 11, 2017 12:52 am

Sander is right. Rolling shutter is pretty much impossible to track. Plus, it's always a good idea to remove lens distortion before tracking and compositing.
There are a few tricks to get rid of rolling shutter, but obviously de-warping the image always comes at the cost of image quality.

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Re: 3D camera tracking in Fusion or other

Post #4 by silean483 » Wed Oct 11, 2017 7:36 pm

Thanks all. I have read that people experience rolling shutter issues even on Red Epic plates. Is the better (opposite) of rolling shutter called global shutter? What is the lowest priced global shutter 4K camera that you know of? Can global shutter plates therefore track and camera solve better than rolling shutter plates?

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Re: 3D camera tracking in Fusion or other

Post #5 by Miltos » Thu Oct 12, 2017 5:35 am

A global shutter camera is not necessarily better in image quality compared to a rolling shutter one. So maybe it will be better for tracking but not acceptable for the rest of the work.

The DJI Phantom 4 pro has a global shutter camera for example but if it was possible to mount your GH4 on it i would use the latter instead.

I have a RED EPIC and never had a problem with tracking a shot. The old RED ONE before the sensor upgrade (MX) probably had some rolling shutter issues but even with that one i had shots that tracked fine.

In your case (speed booster on the GH4) the only difference is the shift in focal length and some additional light concentrating on the sensor. The 3D tracker will not know the difference. Every speed booster has a number that marks that shift so you can even calculate what focal length is simulated if you need to add this to the 3D camera tracking node.

I think you will have zero problems in tracking shots coming from a GH4. My advice is to do a test before principal photography so you feel comfortable with the worflow and use tracking markers when necessary.

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Re: 3D camera tracking in Fusion or other

Post #6 by Midgardsormr » Thu Oct 12, 2017 8:35 am

SirEdric wrote:Sander is right. Rolling shutter is pretty much impossible to track.


I wouldn't go that far. Sure, if you've got massive jello effect going on you'll have a hard time, but any reasonably well-made camera that is well-controlled (not hand-held or mounted on a dirt bike, for instance) should produce trackable footage. We track Alexa and Red footage all the time, and those are both rolling shutter cameras. The only times we really have problems are in very fast pans, and those would be troublesome even with a global shutter due to the motion blur.

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Re: 3D camera tracking in Fusion or other

Post #7 by SirEdric » Thu Oct 12, 2017 9:25 am

Well, I was unclear then..:-)
I did mean the Jello effect when talking about rolling shutter.
Obviously, if the effect does not show up because the camera is well operated,
the tracking would work as with any other footage...:-)

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