What is it called when a person is cloned as different people in a shot?

[Fred Finn]

What is it called when a person is cloned as different people in a shot? And what is the best way to achieve it? I have two clips from the exact same camera location one has me on the right the other has me on the left. How do i combine these without a ghost looking me? I've seen it done... i just can't figure it out? Does one of them have to be blue screened????

Please say no :)

[Robert Knecht Schmidt]

One doesn't necessarily have to be blue-screened so long as the camera wasn't moved and the lighting conditions didn't change. Unfortunately, this is rarely the case, since most novices touch the camera to pause it between takes, and the sun's position in the sky and/or passing clouds make for minute but detracting lighting differences in uncontrolled situations.

But given a perfect match-up between the two parts of the shot, it's just a matter of masking, which can be accomplished in any compositing package like After Effects or combustion.

I don't think this has a conventional name. You can't call it "cloning" as this term already has specific application to a special effects paint tool. I submit for comment "the multiplicity effect" in honor of the Harold Ramis comedy.

In Back to the Future Part II, the scenes involving multiple Martys and multiple Biffs were accomplished with a specially-built motion control camera. The effect was not perfect, and the method was abandoned for Part III, in which the second Marty was shot on a blue-screen stage and composited into the location footage in post.

[Fred Finn]

I second your nomination to avoid confusion with the little stamp tool adobe coined. And thanks for your help, the video matches up light and position shot it in 5 minutes... And I'm using a steady tripod via the school. Just a matter of playing around with it...

[Robert Knecht Schmidt]

Right, I recommend not pausing the camera at all, or doing so with the remote control if necessary between set-ups, so as to avoid touching the camera. The daintiest nudge will set it off-kilter ever so slightly and ruin the effect. Other things to watch out for:

- Overlapping elements--frizzy hair and tiny nooks and crannies are the most difficult to mask
- Doors that have changed position between the two takes
- Reflections that may differ between the two takes--not just in mirrors but in any sort of reflective surface: eyeglasses, drinking glasses, window panes, shiny floors, chrome, etc.--it's easiest just to remove any offending reflector from the set
- Shadows, the same vein as the above, except everything "reflects" shadows, so you'll need to compensate with lighting control, camera angle, and choreography
- Any other interactions between the two yous will need to be carefully staged--make use of foreground elements passing (or panned) in front of the action to provide wipes

Here's an example of a USC student film that attempted this effect but didn't anticipate some of the above problems.

[Fred Finn]

Yeah I'm doing this to learn now so that I know how to do it for future projects. It's only for myown viewing, The problem i'm having is how to blend the layers, or mask, or what i'm supposed to do so that the two shots blend together bringing forward each of their piece equally without making the image look like a ghost.

[Robert Knecht Schmidt]

Well, you paste one layer on top of the other, giving preference to the shot that contains the foreground the majority of the time, and then with a mask, cut this the foreground down to the largest section of the frame you can get away with including.

It's a manual process that involves moving mask nodes around--there's no magic way to accomplish it with a filter. Use keyframing to assist you by masking the first and last frames of the shot, then divide and conquer--keyframe at the halfway point of the shot, then 1/4 and 3/4, then 1/8, 3/8, 5/8, 7/8, etc. Eventually your time resolution will be fine enough that automatic keyframing will have moved the nodes for the rest of the frames around satisfactorily. Look for trouble spots by reviewing the result frequently and correcting the most obvious mismasking.

[Fred Finn]

Thanks, thats exactly what i needed!

[Fred Finn]

Ok, I played with the mask options after researching it in Creating Motion Graphics in after effects. The problem i'm now having is allowing the images to play over the top of one another concurrently!!!!!!!

[Robert Knecht Schmidt]

Sounds like you're using After Effects. Just line up the two clips in the timeline so they're synched as you want them to be.

[Rob Lohman]

It's called "crowd replication"

[Fred Finn]

Thanks second Rob, First Rob, yeah I got that pary I'm pretty good with AE for the most part... Just trying to get information on the specifics of this (if someone has done it before) so I don't have to waste 6 hours messin around with it tryin to get it down... You know what I mean.

[Charles Papert]

Another industry term is "tiling", such as copying a crowd in a stadium and filing in empty sections.

[Filip Kovcin]

if you want to try the same "cloning" thing with the MOVING camera - i can suggest you an old trick... he, he.
this one is not very well known.

1) the most important thing is VERY VERY VERY stabile tripod for your camera, and good dolly with proper track.

2) you will need CD player or DAT tape player as reference for yourself/grip during the dolly movement.

3) make looooooooong paper ruler (say 10 meters long, 20cm wide - sorry guys i do not know inches), at least the distance you want to move your camera

4) mark EQUAL distances (i found that 25cm is ok for normal - not too fast movement) on the paper ruler.

5) record to LEFT channel of CD or DAT tape short "beeps" (one frame long) on a certain duration (say 1 minute). one frame beep is heared every second. (beep-silence-beep-silence-beep-silence-beep--- etc.)* prepare this on FCP or avid dv. it's very easy, uze 1HZ reference tone for :"beep", and then record this as AUDIO to LEFT channel !!!!!

6) record using the similar technique your own voice COUNTING seconds i.e. 1,2,3,4...58,59,60 and put that on RIGHT channel on the very same CD or DAT tape.

7) SUPER FIX your camera on your tripod.

8) SUPER FIX your tripod on your dolly.

9) put the paper ruler along the track

10) turn on CD or portable DAT - hear the sound.

11) mark your paper ruler with proper numbers from 1 to 60

12) move your camera, read the numbers and hear the counting and beeps. the important thing is to be at BEEP on very exact line number of your paper ruler. when hear beep - you are on the line - not between.

if you movement is corresponding to all of this - you are ok. if you are, say on 1st beep on the 1st line, 2nd beep on the 2nd line etc. you can say that your cloning will work.


i did this several times, and this works perfectly. add some time to practice this. this is VERY tough and PRECISE job. do not ignore small differencies in the camera position - it will occur on the screen later.

hope this can help someone, as it helpes me to have nice shots.

filip



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*silence lasts for 29 frames (NTSC), 24 frames (PAL) or 23 frames (film/24p)

[Rob Lohman]

That's a very neat idea indeed Filip. Tough job, but I can imagine
it working beautifully. Probably not usable for lots of passes
though.

Thanks for sharing that!