HOW TO COMBAT ROLLING SHUTTER WHEN FAST PANNING...

[Patrick Fougere]

Hello everyone,

Just a quick question and opinion on how to combat rolling shutter when running and gunning a fast moving scene. I was looking for your input on settings used, frame rates, shutter angle's, iso, etc... and or your personal techniques.

Thanks-

Patrick Fougere

 

[Robert Hart]

Look at the opening of the film "Get Out".

You may observe in the forest shot from the moving vehicle after the kidnap scene that the camera view may have been dutched to make tilted passing trees appear "upright" whilst the vehicle itself is moving laterally relative to the shot up or down a slight incline.

I may also have been over-thinking this and there may have been a simpler solution, that of editing out the best pieces out of a long pass along a wise choice of undulating landscape. Then again I might just be full of disinformation. At least that is what I interpret.

Better and more skilled practitioners than I will analyse more accurately than I can. It has been about three years since I played with this issue. If the opening was shot with a film camera, Blackmagic "big" URSA ( global shutter ) high frame rate slowed down or Red's own motion mount, shutter skew might be minimal or avoided altogether.

My try of dutching with the SI2K before I saw "Get Out", - was with light poles and sloped ground but the pan speed must be consistent. You only have about a 50 degree arc of pan movement across the slope before the vertical objects go out of whack as they become more vertical in the natural view uphill and downhill. With varying pan speed and practice you may extend that arc a little. Longer lenses with narrow field of view and soft backgrounds may be your friend. -

Some other commentators here might like to examine whether using the slowest shutter available for motion blur would help versus the tendency for the skew to be worse - or electing the faster shutter and taking the hit of stuttery motion and inferior performance in low light.



Good luck with your endeavours and keep us posted on how it turns out for you.

 

[Robert Hart]

My personal preference might be to have all action and camera movement like chases and fights choreographed and laid out to occur towards or way from the camera when lots of background is visible. If you have to go close with a longer lens, then try to avoid sharpish focus on background straight upright objects like wall corners and doorways.

 

[Jordan Beard]

Just from playing around with the panning speed tool for a minute it seems like shooting with a wider lens and a higher framerate will make rolling shutter less pronounced. That might not be super helpful because those impact the look and feel of your scene. From what I understand about rolling shutter, shooting with a smaller sensor crop could also reduce the effect.

 

[Patrick Fougere]

Just from playing around with the panning speed tool for a minute it seems like shooting with a wider lens and a higher framerate will make rolling shutter less pronounced. That might not be super helpful because those impact the look and feel of your scene. From what I understand about rolling shutter, shooting with a smaller sensor crop could also reduce the effect.

I see what your saying with the smaller sensor crop! That makes sense...

What I was thinking was either: Film at a higher frame rate, with a 180 deg. shutter angle or more. Then reduce the frame rate in post, and add a very light motion blur to hide the crisp shutter angle. I wonder if REDCODE would effect rolling shutter?!?! I'll have to test that...

Jordan, I'm wondering why you would think a wider lens would lessen the effect. or are you saying the combo of the lens and the increase of shutter speed would do it?

 

[Patrick Fougere]

My personal preference might be to have all action and camera movement like chases and fights choreographed and laid out to occur towards or way from the camera when lots of background is visible. If you have to go close with a longer lens, then try to avoid sharpish focus on background straight upright objects like wall corners and doorways.

Like a chase scene where the subject is looking back at the chase car and then the chase car is looking forward at the target car. That way you still get the "HIGH CHASE" feel without the side to side action. I get what your saying. HUUmmmmmm....

I like where your head is at Robert....

 

[Patrick Fougere]

Look at the opening of the film "Get Out".

You may observe in the forest shot from the moving vehicle after the kidnap scene that the camera view may have been dutched to make tilted passing trees appear "upright" whilst the vehicle itself is moving laterally relative to the shot up or down a slight incline.

I may also have been over-thinking this and there may have been a simpler solution, that of editing out the best pieces out of a long pass along a wise choice of undulating landscape. Then again I might just be full of disinformation. At least that is what I interpret.

Better and more skilled practitioners than I will analyse more accurately than I can. It has been about three years since I played with this issue. If the opening was shot with a film camera, Blackmagic "big" URSA ( global shutter ) high frame rate slowed down or Red's own motion mount, shutter skew might be minimal or avoided altogether.

My try of dutching with the SI2K before I saw "Get Out", - was with light poles and sloped ground but the pan speed must be consistent. You only have about a 50 degree arc of pan movement across the slope before the vertical objects go out of whack as they become more vertical in the natural view uphill and downhill. With varying pan speed and practice you may extend that arc a little. Longer lenses with narrow field of view and soft backgrounds may be your friend. -

Some other commentators here might like to examine whether using the slowest shutter available for motion blur would help versus the tendency for the skew to be worse - or electing the faster shutter and taking the hit of stuttery motion and inferior performance in low light.



Good luck with your endeavours and keep us posted on how it turns out for you.

DAMN.... The connection here in TX over my phone sucks, and I can't really see the video in good quality to even see if there is any rolling shutter.

I wonder if you get the same effect if you tilt up too fast? You think you would get a crunching / stretching effect instead of a bend effect when you pan?

 

[Robert Hart]

I like where your head is at Robert....

Having it securely plinthed upon my shoulders, free to swivel 180 degrees without the sound of cracking joints to spoil the audio ( yet ) does me just fine. My backside being pointed daily towards China is a bonus.

I have been tempted to get swaddled up in all manner of padding and head protection, strap an operating and pre-focused camera inside a pillow with a wide lens on front and step right in the epicentre of a nice violent fight scene, following the choreographed action inside, exiting and entering through the brawlers and orbiting around as the melee works its way along a street, scattering when the sirens arrive, then following the runaways.

At my three-score and ten years, I no longer have the agility or courage to go that one. The last time I tried an improvised crane from ground to shoulder height hand-held at an event, I tumbled over backwards when my ankle-joint locked. Got to love having a quick-thinking offsider who I handed the cam to and who kept on filming.

 

[paulcurtis]

Hello everyone,

Just a quick question and opinion on how to combat rolling shutter when running and gunning a fast moving scene. I was looking for your input on settings used, frame rates, shutter angle's, iso, etc... and or your personal techniques.

Thanks-

Patrick Fougere

If you're willing to loose a bit of resolution there are post tools that can help rectify this. They work much better on panning shots like the opening to Get Out because they can just skew the image the other way. The amount of rolling shutter is fixed for a particular camera.

A slightly more advanced tool is a consumer stabiliser called Mercalli Pro and it can work wonders with jello and rolling shutter as it maps the sensor and all forms of jello (vertical compression as well). It's an utter pain to use but sometimes can get you out of a sticky situation. It's doesn't always work though!

cheers
Paul

 

[Björn Benckert]

SteadXP can post improve rolling shutter in a good way even when there is nothing to track on.


But to me if you got rolling suhutter issues then you are simply moving the camera to fast. Dampening, stabilize and pan slower... It´s not really to avoid the problem but in general I hardly ever seen nice camera movements that has rolling shutter issues but I seen a lot f ugly camera movments that have.

To me the new short, small and lightweight cameras makes quite ugly moves when hand held. A large / long and heavy camera moves comletly different and alos with todays resolution and the Cmos motion blur its so many things that makes shaky cameras something to watch out for and avoid or atleast work with to get it right.

Motion mount is a good start, and a big heavy camera is key.

 

[Chris Jordan]

My personal preference might be to have all action and camera movement like chases and fights choreographed and laid out to occur towards or way from the camera when lots of background is visible. If you have to go close with a longer lens, then try to avoid sharpish focus on background straight upright objects like wall corners and doorways.

This has to be the most creatively gutting suggestion ever.. Yet, it's true. Creating scenes around your gear is a sad day.

 

[Robert Hart]

(QUOTE) Chris Jordon - This has to be the most creatively gutting suggestion ever.. Yet, it's true. Creating scenes around your gear is a sad day. (QUOTE).


I guess the corollary to all this might be to make the camera moves hand held and very aggressive with lots of roll ( dutching ) to bury the rolling shutter skew in oblique angles. The time and place for this may be very limited but who knows?

It comes down to what is appropriate to the story. If the "art" is drawing attention out of the storytelling to itself for its own sake, then the job has not been done properly.

The old adage "not because you can but because you should" holds as true as ever.

I am sorry to be picking on a Netflix show titled "Altered Carbon". It is apparent that the makers had sincere heart and worked their backsides off to realise the writer's vision.

I find myself having to whip myself back into the story by needless distractions. I am forced to strain my hearing sense to pick up what seems to be poorly recorded dialogue. I can live with that eventually.

Equally however, I find myself distracted out of the story by visual "break-the-rules" gestures like non-motivated no-nose-room framing of humans, non-motivated out-of-framing with a left frame edge deadcentre clean through a face in close-up seen directly from front. These had me immediately thinking, "did they have to crop out some idiot who walked in on the shot unseen" or "did somebody leave their jacket hanging on the set".


The audience is the final editor. - So long as a technical deficiency does not take away from a story's flow, then audiences may forgive it.

 

[Eric Lange]

Hello everyone,

Just a quick question and opinion on how to combat rolling shutter when running and gunning a fast moving scene. I was looking for your input on settings used, frame rates, shutter angle's, iso, etc... and or your personal techniques.

Thanks-

Patrick Fougere

I agree with Bjorn on this...

If you have constant velocity* moves , either angular or linear this will iron out your "Jello" to a linear shear.

On the other hand if your camera and imagery is fritzing out as result of battle conditions/taking heat then that can also have an enhanced "Dramatic effect"... There's a certain amount of honesty in that that your audience will be able to feel. [As you know over the past 100 years so many news reels from WWI and WWII for battle scenes were staged after the fact, and passed off as the genuine article.]. If Your footage is "wonky" and on the "Blink" it is for good reason. The camera "feels it" too.

______________________________________________________________________________________________________________________________________________________________________________________________________________________


*When I was at Cambridge (quite some time ago) there was a professor in the Geography department/GIS that was flying high resolution multi-spectral instruments that would scan. So naturally when the aircraft takes it's pre planned flight path this displaces the scan in a similar way to "Rolling shutter"; so they were able to grab the avionic data for attitude, altitude, heading and velocity and then reconstruct the scan lines into a non-sheared image... Like what some folks are saying you have to crop in a bit. That relies on the fact your scene is a solid object/constant shape. I'm sure some bright spark has probably figured out how to pull data from a motion stabilization rig to accomplish similar things (maybe)?

@PF noticed you changed your title... (Good move as there IS more that can be done) ... versus random frenetic camera moves. "Run and Gun"...

_______________________________________________________________________________________________________________________________________________

---> "Brain-fart" If you have constant-ish** velocity pan there should be some pattern matching techniques that find similar features from scan line to scan line and then geometrically slide the scan lines back to their original intended positions (i.e. you may not have to grab position and orientation dynamic data from a motion rig?). I have no idea how the RED Motion mount works to 'Combat" jello (there are a few threads about that) ???? I have to find that out at some point I guess. ;-) [Personally I LIKE slow pans ]. I guess with a fast pan you may be tracking an object so I guess the object you are tracking won't "Jello"... but the background might? [That might be really cool effect in of itself].

_____________________________________________________________________________________________________________________________________________

** For motion control systems and machine tools "acc" and "dec" (acceleration and deceleration is a big deal and even changes of dynamic acceleration)... So obviously when you start your pan you have to accelerate upto your intended angular velocity and then after you have achieved the constant angular velocity you want decelerate (unless you just want to keep spinning round in circles lol), So obviously snip off the footage at either end of your pan and plan to start somewhere before and after subject area you want to capture. I know that's painfully obvious to someone with your "Smarts".

 

[Eric Lange]

DAMN.... The connection here in TX over my phone sucks, and I can't really see the video in good quality to even see if there is any rolling shutter.

I wonder if you get the same effect if you tilt up too fast? You think you would get a crunching / stretching effect instead of a bend effect when you pan?

I don't know what the strict definition of "Dutch" or "Duch angle" is , but maybe turning the camera sideways (rotation 90 degrees on its optical axis) would at least mean with a fast pan you won't get shear (just a bit of stretch/compression ), and if you are tracking an object the object should be geometrically more "correct" ..? Kinda what Robert Hart was saying. I'm sure you'd like to build an improvised rig for that... Got to have some fun. [Bear in mind the image is upside down to begin with, so you may discover if the sensor scans bottom up or top down (so you get a different effect if you pan left to right or right to left and the camera is 'Dutched"/rotated CCW to the left or is leant over CW to the right, that will effect geometric compression of the image versus stretching... You could have some fun with that. ]. I still want to see a Tank barrel be used as a motion stabilization rig Just remember no firing... (I'm sure you could get some great shots ... photographically (that is) ).

Are you tracking fast moving tanks, helicopter gun ships or slow moving projectiles... Just wondering what the imagined situation is? Camera mounted to a turret (of a tank?) or some other hardware?

Lets say your "Fast pan" is a quarter of a second and you are shooting 120 fps, that's only 30 frames ... So you can do a lot of 'Hand work" in post to fix and correct compression and distortion without a lot of key framed automation and batch processing... If you have long boring nights there hell you could even fix this in a low end version of photoshop in a few evenings if you had to lol.

 

[Patrick Fougere]

I don't know what the strict definition of "Dutch" or "Duch angle" is , but maybe turning the camera sideways (rotation 90 degrees on its optical axis) would at least mean with a fast pan you won't get shear (just a bit of stretch/compression ), and if you are tracking an object the object should be geometrically more "correct" ..? Kinda what Robert Hart was saying. I'm sure you'd like to build an improvised rig for that... Got to have some fun. [Bear in mind the image is upside down to begin with, so you may discover if the sensor scans bottom up or top down (so you get a different effect if you pan left to right or right to left and the camera is 'Dutched"/rotated CCW to the left or is leant over CW to the right, that will effect geometric compression of the image versus stretching... You could have some fun with that. ]. I still want to see a Tank barrel be used as a motion stabilization rig Just remember no firing... (I'm sure you could get some great shots ... photographically (that is) ).

Are you tracking fast moving tanks, helicopter gun ships or slow moving projectiles... Just wondering what the imagined situation is? Camera mounted to a turret (of a tank?) or some other hardware?

Tilting the camera 90 Deg. would change the liner track from hor to Vert.... That's a great Idea.

As far as What I plan to shoot; Med-evac ops, Interview style footage about different MOS (jobs) in the Army. Hell I just might have some fun with the camera and make a generic HOOHA video LOL. But right now my heart sit's in dramatic, artistic look. The kind of film where the dialog and the cinematography both tell a story. I'm just trying to head any problems off at the pass, which is why I wanted everyone's opinion on how they combat "rolling shutter".

Thanks for your input Eric.

 

[Eric Lange]

Tilting the camera 90 Deg. would change the liner track from hor to Vert.... That's a great Idea.

As far as What I plan to shoot; Med-evac ops, Interview style footage about different MOS (jobs) in the Army. Hell I just might have some fun with the camera and make a generic HOOHA video LOL. But right now my heart sit's in dramatic, artistic look. The kind of film where the dialog and the cinematography both tell a story. I'm just trying to head any problems off at the pass, which is why I wanted everyone's opinion on how they combat "rolling shutter".

Thanks for your input Eric.

No worries,

That's kinda how I think and design projects (as well), particularly new field projects is just try to predict every problem I can up front and design around that without having "Catastrophic thinking"... If you do that then you close a large percentage of problems meaning you can solve the remaining 7 to 15 % that no one could ever predict in advance as compared to being blindly optimistic and being blind sided by something that could have been predicted up front. So for me at least that's always been a recipie for success. Preparation is everything to handle the unexpected as far as anyone can. I'm sure you are very experienced in planning and preparing complicated things.

Like your style of thinking. Cool your wife (reading the other thread has the Camera that RED shipped) ... I'm so happy RED could do this; sounds very worth while and pretty psyched for you too.

_________________________________________________________________________________________________________________________________________________________________________________________

Well if it's more MOS based and interview type stuff and artistic look, then probably the need for super fast pan goes substantially down. And don't forget there may be some things you can fix "in post" (can't believe I'm saying that) when you get home or when you have time. It has made me look at the RAVEN gear more closely and it IS a really really nice package for the $. Perfect.

 

[Hrvoje Simic]

As far as What I plan to shoot; Med-evac ops, Interview style footage about different MOS (jobs) in the Army. Hell I just might have some fun with the camera and make a generic HOOHA video LOL. But right now my heart sit's in dramatic, artistic look. The kind of film where the dialog and the cinematography both tell a story. I'm just trying to head any problems off at the pass, which is why I wanted everyone's opinion on how they combat "rolling shutter".

You'll get the feel for panning speed pretty soon and intuitively adapt the camera motion.

Pulling your own focus for unpredictable real time action will take more time and effort.
Make sure you set up a comfortable, balanced and practical shoulder rig so you can run around with minimal fuss.

 

[Patrick Fougere]

You'll get the feel for panning speed pretty soon and intuitively adapt the camera motion.

Pulling your own focus for unpredictable real time action will take more time and effort.
Make sure you set up a comfortable, balanced and practical shoulder rig so you can run around with minimal fuss.

Thank you for the advice Hrvoje, I know its going to take me at least a month to really LEARN my Raven. After that I'm going to buy the pieces to build a rig. I already know what my biggest problem is going to be with pulling focus; that's remembering WHICH WAY TO TURN THE DAMN THING. LOL I know Im going to screw that up at least a dozen times!!!

 

[Patrick Fougere]

THANK YOU

To everyone who has put in their .02 worth in. You've all given me a lot to think about and plan.

Please if you guys think of anything else, keep it coming. I love to learn!

-Patrick