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8k for stabilization


Thomas McNamara

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Hey everyone,
 
Wondering if anyone can help with this. 
 
I'm shooting a project on my Helium 8k in 8k WS and I'm going to want to stabilize in post. I'm looking for the best way to achieve this. I've heard of the technique of framing for 4k in the monitor and then scaling in in post to find that "framed for 4k" shot value and then stabilizing.
 
So, utilizing this technique, is any normal stabilization within commonly used NLEs (like stabilization within fcpx or warp stabilizer in Premiere) the best way to stabilize given all that extra room? Or is there another, better way? Also, how do I frame for 4k WS (or any other lower resolution than 8k WS) in the monitor? Couldn't seem to find how to do that. 
 
And also, how do I get a mathematically perfect match for the 4k WS frame in post when I drop the clip in the timeline? Do I just approximate that frame by scaling in until it looks correct?
 
Thanks for the help! 
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I wouldn't necessarily shoot that much wider a shot than you're looking for. You only need to give it enough room to slide around slightly. It depends how much instability you're looking to remove.

When I'm stabilising shots, I tend to do it in After Effects using the inbuilt tracker (or Mocha if the track is tougher, but that's rarely necessary.) Then, you can stabilise the whole shot to a single point, and essentially re-design the camera move to your whim by sliding that point around, within the limits of how much extra frame you've got.

There's no mathematical precision involved but the results can be quite nice. You can pull off those Fincher-style super-precise framing tricks - I'm not sure if perhaps he's actually doing it that way.

Bear in mind that if your instability is very fast-moving, you may end up with motion blur in the frames which cannot be stabilised-out.

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Hi Phil! 

 

Thank you very much for the reply! Good to know I don't need to scale in that much for an effective stabilization. I'll look into stabilizing in AE. 

I'll actually be shooting this with a fairly wide lens on a Ronin 1, so there wouldn't be much to stabilize, I just want it to be steadycam steady (budget cut my steadicam operator). 

So for the frame guide in camera, would you suggest to crop by eye and then later scale in post to match the frame guide? 

Thanks again for your informative answer! 

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David Fincher uses 20% look around when setting up the frame lines. (see pic)

Many cameras/field-monitors allow custom frame-lines to be set up. Some cameras will give you a 10% safe area frame-line option

Or you can make your own with masking tape or a chinagraph pencil directly on the screen. If you want to work out the correct size for the frame lines this way. Print out you frame on paper e.g your composed frame within a 16:9 rectangle, point the camera at it and then trace the framelines on the screen/monitor/viewfinder. It won't be pixel accurate but close enough. 

You can of course eyeball it, but then your going to have to do different resizes on each shot in post. I'm sometimes lazy and will guess at 2.39:1 composition on a 16:9 camera, is usually fine - but I do find I have to adjust the shot position in post a bit more.

Better to compose using an actual frameline. Then you can automate the crop in post and if your working with an editor it takes any guess work out of the equation. 

 

Girl-with-Dragon-larger-negative-size.jpg

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On 6/5/2019 at 7:52 PM, Phil Connolly said:

David Fincher uses 20% look around when setting up the frame lines. (see pic)

Many cameras/field-monitors allow custom frame-lines to be set up. Some cameras will give you a 10% safe area frame-line option

Or you can make your own with masking tape or a chinagraph pencil directly on the screen. If you want to work out the correct size for the frame lines this way. Print out you frame on paper e.g your composed frame within a 16:9 rectangle, point the camera at it and then trace the framelines on the screen/monitor/viewfinder. It won't be pixel accurate but close enough. 

You can of course eyeball it, but then your going to have to do different resizes on each shot in post. I'm sometimes lazy and will guess at 2.39:1 composition on a 16:9 camera, is usually fine - but I do find I have to adjust the shot position in post a bit more.

Better to compose using an actual frameline. Then you can automate the crop in post and if your working with an editor it takes any guess work out of the equation. 

 

Girl-with-Dragon-larger-negative-size.jpg

 

Phil.. why does he do that.. 

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who Fincher? I think its down to wanting perfection. Watch his recent films, the operating is flawless - better then is possible by a great operator, because its a combination of a well designed shot, good operating and post tweeking.

I think the idea is if the technique is perfect, no wobbles etc... its invisible. 

Shooting with look around is just part of that strategy, its not about saving decisions till post, but if a shot needs to be post stablised you've got the room to do it without effecting the intended framing..

Its good for post as well, things like tracking markers can be placed outside the frame - save's having to paint them out

Also if you've got an 6 to 8K camera - you can go for a big crop without having too much of a quality impact

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I personally don't like automatically shooting wider then necessary for a "pushin" because it has a longer lens feel to the finished product AND you're pushing the imager and glass a bit more. I shoot with the dragon a lot and have experimented with shooting in 6k for a 4k finish and the look difference is pretty dramatic if you do the push in post. I don't know why, but it's always noisier and softer then shooting straight 4k in the camera. Same goes for 4k shots you zoom in to 3k for a 2k delivery, same problem. It's very odd. 

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4 minutes ago, Tyler Purcell said:

I personally don't like automatically shooting wider then necessary for a "pushin" because it has a longer lens feel to the finished product AND you're pushing the imager and glass a bit more. I shoot with the dragon a lot and have experimented with shooting in 6k for a 4k finish and the look difference is pretty dramatic if you do the push in post. I don't know why, but it's always noisier and softer then shooting straight 4k in the camera. Same goes for 4k shots you zoom in to 3k for a 2k delivery, same problem. It's very odd. 

yeah the is a quality hit since bayer cameras are lower resolution then their stated resolution. A 4k camera probably resolves about 3K. You do need to oversample, thats because a 4K sensor is only 2K green, 1k blue and 1k red - its not possible to resolve 4K RGB properly with that data set - the software has to interpolate.

A 20% crop on 6k - gives nearly 5k. So thats more then enough for a 2K finish and not too bad for 4K.  I guess they sought a balance between post flexibility and quality.

I suppose on the lens thing, its a different feel - but lots of RED's have larger sensors so Fincher is just cropping down to around super 35mm. 

Personally I agree with Tyler, I prefer to push for the best quality for oversampling reasons - and believe its important to commit to a framing decision on set. That said you can't argue with Fincher's results his films do look pretty good....

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