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Low Budget Camera Movement for High Speed

Justin Black
 

Hi all,

Have a job coming up that's essentially models doing stuff on greenscreen at 120fps. We're looking to introduce a bit of movement into it (lateral or push-in). This would ideally be done with a Bolt, which we can't afford. How would you approach this? My thinking is to ride on a Peewee dolly and have enough track for the grip to get a running start and decelerate. Anything else I should be considering?

Thanks for your help!

--
Justin Black
Director of Photography
905.808.0433

David Fuller
 

If it were me, shooting models models on greenscreen, I’d shoot them full-frame and do the moves in post.

David Fuller
Director, Cinematographer, Camera Geek
Maine, USA
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On Apr 7, 2018, at 12:44 PM, Justin Black <contact@...> wrote:

Hi all,

Have a job coming up that's essentially models doing stuff on greenscreen at 120fps. We're looking to introduce a bit of movement into it (lateral or push-in). This would ideally be done with a Bolt, which we can't afford. How would you approach this? My thinking is to ride on a Peewee dolly and have enough track for the grip to get a running start and decelerate. Anything else I should be considering?

Thanks for your help!

--
Justin Black
Director of Photography
905.808.0433

cleverson cassanelli
 

in my thinking. if you have a Peewee dolly you do have a budget.
but, 120fps is not a much slow movement
so you can easy shot with dolly

i did this no budget movment at 120fps, with Fs700, lot of times just using shoulder rig.
its very easy and get an organic movement.

120fps is not a very slow for people


--
Cleverson Cassanelli

diretor de fotografia
11 96635 0917
São Paulo

Rachel Dunn
 


This is a good solution, provided you have enough resolution.  

If delivering at HD, UHD will give you a maximum 250% digital push in.  6k will give you close to a 400% push in.

That’s the only caveat.

Unless you have motion trackers on the wall, and require the background to match the camera move exactly, your dolly move will actually complicate post.  It doesn’t sound like thats what you need to do.

It is very difficult to see motion of a subject against an unmarked green screen, so a dolly move doesn’t really buy you anything. 

Also, since you are essentially “baking in “ the move,  you may end up painting your client into a corner.

The compositors will end up trying to remove your motion so they can add their own, except the image will invariably be cropped at the most inconvenient places, and have motion blur in the places where you don’t want it.

Much better/simpler/cheaper to do lockoffs -  less exciting on set, but far better for post, because the clients will be able to do anything.

Compositors will add the moves with the appropriate motion blur, and everyone will be happy.

You might also consider a frame rate higher than 120 fps if possible - just like the motion, they can then choose the speed of the subject in edit as well.

- Rachel 


  www.racheldunn.com
        310-562-5779
rachel@...
    



On Apr 7, 2018, at 9:59 AM, David Fuller <david@...> wrote:

If it were me, shooting models models on greenscreen, I’d shoot them full-frame and do the moves in post.

David Fuller
Director, Cinematographer, Camera Geek
Maine, USA
---

On Apr 7, 2018, at 12:44 PM, Justin Black <contact@...> wrote:

Hi all,

Have a job coming up that's essentially models doing stuff on greenscreen at 120fps. We're looking to introduce a bit of movement into it (lateral or push-in). This would ideally be done with a Bolt, which we can't afford. How would you approach this? My thinking is to ride on a Peewee dolly and have enough track for the grip to get a running start and decelerate. Anything else I should be considering?

Derek wiesehahn
 

Just about any dolly move will look smooth at 120fps.

On Apr 7, 2018, at 12:44 PM, Justin Black <contact@...> wrote:

Hi all,

Have a job coming up that's essentially models doing stuff on greenscreen at 120fps. We're looking to introduce a bit of movement into it (lateral or push-in). This would ideally be done with a Bolt, which we can't afford. How would you approach this? My thinking is to ride on a Peewee dolly and have enough track for the grip to get a running start and decelerate. Anything else I should be considering?

Thanks for your help!

--
Justin Black
Director of Photography
905.808.0433

Thomas Gleeson
 

Justin,

Some thoughts as I have had this challenge. A high resolution camera will be helpful but many cameras window their sensor and drop resolution to attain HFR so that needs to be factored in. Unless you are looking for the timeslice look 100fps is plenty slow for most human motion. 
Digitally moving your models in post will work OK for lateral movements but a push in will just feel like a zoom as the perspective will not change. The lateral moves can be enhanced by having your model on a small turntable and have them turned say through 60 degrees to simulate the changing camera viewpoint of the laterally moving camera. For the push in moves you are better off closer with wider lenses so as to exaggerate what camera speed you can manage. The issue here is the safety of the model so I would avoid heavy dollys. A possibility is a lightweight slider configuration hung upside down like one of these from Rigwheels and some scaffold poles. This would keep the rig out of shot and you could push the camera by hand quite fast with little danger.

The nature of perspective is that its mainly a factor when your close so you could combine the real push ins with a digital zoom to create much longer camera tracks. Also combine the turntable and slider push in for more complex “virtual” moves. Make some note of your intent so the post people know what your attempting on each shot. Have fun.





Mark Weingartner, ASC
 

I’ve read a bunch of good suggestions, although the devil is in the details of what you need… how long to the good bits have too be - do you need clean starts and stops etc etc etc

If you want perspective change and angle change you need movement… if you don’t need that then doing the moves in post has some benefit…
…but part of giving a director a chance to direct and a client a chance to feel what you are making for them sometimes involves camera movement
that makes vfx harder… so be it.

But take the time to get some tracking markers on the green screen… I tend to use green ones on bluescreen and blue ones on greenscreen so the compositer has at least
a chance of keying off the trackers without having to paint them off or keep adjusting the garbage mattes.

Idea #1:
Unless you are booming up and down during these fast shots the weight of the peewee is not your friend.
You can lay some straight track and some curved track (think a stylized #9 but not all of it… a bit of straight with a curve at one end…
Use a a flat dolly with a tripod on it, with a box chained down for you to sit on and the focus puller one remote focus… keeps the weight down, simplicity up, and
gives the focus puller a chance because the path of the dolly is set… and yes, I would use a tripod chained or strapped down not a bazooka but that’s just because physics…
Add a couple of sandbags over the wheels if it is feeling a bit rumbly… but bear in mind that if you are using the footage at 120-for-25 the rumble may become a lot less noticable.
If you are comfortable on a geared head this is a great time for it… operate with a monitor and you can avoid some of the acceleration framing issues by using a geared head.

Idea #2 If you can afford a smaller technocrane AND if you are good at backpanning on a remote head, consider doing swinging/telescoping moves back and forth.

You can do this with a fixed-length jib arm also, of course whilst moving the chassis (on track) to make some compound moves, but unless you have a crew that really knows their shit, not a crew that
always wanted to try this, don’t bother… We did do lots of wonderful arcing swinging shots this way before telescoping cranes existed… and then when they were still too expensive for low-budget jobs.

Idea #3 I HAVE NOT DONE THIS… but you might consider a gimbal or even old-school un-stabilized remote head (I have done this) on that tripod on that sled dolly … the pa or runner who has to deal with the cable will get the run-around but you can stay with the monitor and the director and respond to framing discussions

Good luck - tell us how it turned out!

Mark Weingartner
LA based DP
lots of VFX
also lots of weird camera movement
(some of it on purpose)

Rick Gerard
 

This is completely off the wall but what about a MoVI Pro and a Segway? I’ve been getting some pretty amazing stuff and it will go about 8 mph which is a good fast jog...

Rick Gerard
DP/VFX Supervisor
MovI Pro / Licensed Commercial Pilot Fixed Wing and UAV
Northern CA

Justin Black
 

Many thanks for everyone's input! Love CML

Thomas/Mark got it with the perspective change. With the wide shots we'll certainly add movement in post, but it's about spicing up medium shot of a dress blowing with some rotational movement and other such things. 

Nice to get some high end validation on the doorway dolly. My only high speed dolly moves have been with that setup due to budget, and I was surprised at how well it worked.

The turntable idea is also interesting in the right circumstances (angle of light, talent blocking, etc).

The storyboards are still being settled so it may indeed all be safer lock-offs, but the knowledge/perspective is valuable. Thanks everyone.

--
Justin Black
Director of Photography
905.808.0433