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Moving Time Lapse

Saw a wonderful time-lapse, panning shot. I have done a few static time lapse shots but never moving shots. What is the method to a smooth, in-sync pan during a multi-hour time lapse?


Walter, I just bought an incredible stepper-motor head from Sam Dodge!!! It is a re-built gear-head, Mitchell based, which has had the wheels removed and replaced with stepper-motors. There is a control box rigged to the back with directional switches and speed dials. Basically, once you figure the duration of the shot, and the direction/duration of the degree of movement, you simply set the dials accordingly and sit back with a cup of coffee [or iced-tea if it's me] and wait for great things to happen! Of course, I would gladly rent this unit to you for a very low CML discount :-) I paid around $4K for the head, and I had it modified with an input connector so I can interface the driver boards with my laptop for future pan & tilt Mo-Co applications. But I still am waiting for some decent [and simple!] software. I hope this answers your questions. Jeff Barklage PS, this is a 12vDC system and can be operated as a 'stand-alone' unit, no laptop needed, jut a set of sticks.


There is another way ... it involves a geared head and it's VERY boring ...

Justin


You forgot to mention the camera tape and the marker pen.

Hey! it was only 6 hours

Geoff


Yes, I am familiar with that method as it is obvious when a pan has somewhat of an unsteady motion. I was not aware that a machine could perform the move.


Other than the mechanics involved, the other obvious necessity is to figure how long the pan must be in screen time and how long that translates to real time.

I recently did a shot with an intravolometer and a dolly move. But the shot was designed to only last about 6-7 seconds of screen time as I recall and we were shooting something like every 2 second intervals. So we shot for about 13-15 seconds real time. And we just hand-pushed it on a pipe dolly. It wasn't the smoothest dolly but totally acceptable and fine for our needs.

Jim Sofranko NY/DP


>There is another way .... it involves a geared head and it's VERY boring

>Yes, I am familiar with that method as it is obvious when a pan has somewhat of an >unsteady motion. I was not aware that a machine could perform the move.

Walter I take that as a personal INSULT !!!! MY time lapse pans are NOT wobbly

Justin "Bolex's at dawn" Pentecost


Depending on the amount of pan, you could shoot wide, scan the imagery, and pan in post via a digital move. If more imagery were needed a vista-vision format camera could provide more negative to move within. I know, it's digital... Or a simple motion control camera, track, head setup could easily accomplish this as well... and all the imagery would be original negative, no digital imagery needed. Peter Weiss


Louie Schwartzberg has a motorized, geared head for this purpose. It is very old, made by Mitchell camera people I think. It allows him to preset pan and tilt speeds and have the camera head move very slowly while he shoots timelapse. He does it all the time. He can program "ramps" that slow down the start and stop so the beginning and end of the moves are natural-looking. Quite an impressive rig, considering it is about 60 years old.

-- Jim Dollarhide


Recently did some time-lapse work for a spot where we were shooting city traffic at 1fps. I had good luck with some short pans using an O'Connor 2575 set to very high drag.

BTW we were test-driving the new time-lapse setup for the 435 and it jammed so many times that we gave up on it. The little tongue that unwinds into the gate would get stuck on something. We thought it might be a door alignment problem but when my assistant checked with Arri they said it had something to do with a variation in some 435's that had to do with gate being slightly different. ?? Well my info on this is sketchy so I'll stop. Anyway if you use it check to be sure this problem has been corrected. My assistant said that Arri was pursuing the problem.

If anyone has better information on this, I hope you'll make things clearer than I just did.

Norman Bonney


I had a very similar problem when i was shooting time lapse with James (Welland) very wierd. Panavision told me it was a software fault with the controller.

Justin


Cineon has a function called "cinespeed" which does a very clever motion-vector based varispeed, which it allows it to in-between frames, actually inventing new images rather than mixing surrounding frames or step-printing as is normally done. It's fairly slow (i.e. expensive) and doesn't always work perfectly (it depends to some extent on the type of material), but when it does it can be amazing. I've used it to create motion blur by inventing extra frames and then mixing the result back to normal speed (effectively increasing the shutter angle). I'm sure it could work well for variable time-warp effects without having to overcrank.

It's also used quite often to fill in gaps in time-slice effects - allowing the use of fewer static cameras, so I think it might apply to the moving timelapse application as well - shooting half (or less) the frames neccesary for the duration of the shot and in-betweening with cinespeed would potentially give a smoother result than attempting the whole move by hand, although for the cost motion-control might be comparable, or digital stabilisation would be simpler if its a nodal pan or tilt. Much better to take the in-camera route if possible, of course!

Tom.

-- Tom Debenham Visual Effects Designer Computer Film Company,


The best moving timelapse shots are accomplished with a motion control unit. The motion control software not only moves the head/dolly just as smoothly at single frame as real time, but it also controls the camera on a time/frame basis with built-in intervalometer routines. I use Kuper Controls software, and with it I can program continiously running shots at s;pw frame rates, or I can make a traditional intervalometer shot where there is a constant interval and exposure time. Additionally, you can also program the interval to change the time compression during the shot; and the exposure time, (even the shutter or iris) to widely vary the exposure, as one might like to when shooting a sunrise.

Don Canfield

Gear+Rose Motion Control


 


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