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-   -   DIY timeslice effect - MATRIX (https://www.dvinfo.net/forum/alternative-imaging-methods/60334-diy-timeslice-effect-matrix.html)

Levan Bakhia March 28th, 2006 01:27 PM

Hi Wayne. Thanks for the hint. What about that software you mention? I will not reduce the number of cameras, but the software could still be usefull. :*)

Wayne Morellini March 29th, 2006 04:48 AM

That's the thing, I can't remember, but it is bound to be on some Intel site, try their search functions.

Re-edit, just looked for an hour or two, haven't found it yet, but was Intel based.

Levan Bakhia April 2nd, 2006 04:03 AM

So, I have ordered the cameras, and it will be with me within next 2 weeks. Some guys are building a sync system. For the begining I will only be able to triger all the cameras at the same time, but they will develop the software so that I could trigger the cameras with selective time delay.

Now I have to think about the rig. Do you have any suggestions? How to build it? I was thinking about buying some support heads and then build a rig where I could screw this heads. So, if you have any ideas please let me know :*)

Cole McDonald April 2nd, 2006 10:04 PM

The guys from sequential pictures did a send up of the matrix with some slo-mo-ish low budget work in it...I think they just invested in a tennis ball and some string...did all the background replacements in Photo shop, but that could as easily be done in after effects.

on the mac, Morphx does a good job for free, and I'm sure there's a PC morphing programming that will do a good job for free as well...I took the frames from the board breaking video up top here...looks really good about 30 mins of work to morph the first 2 frames convincingly in free software.

Levan Bakhia May 15th, 2006 02:35 AM

I recieved all 60 of the cameras. I did the syncronization and it is pretty nice in this aspect, but I have problems with aligning cameras in the right way. The rig. What do you suggest? even slight and unnoticable difference between cameras, makes the final sequence shake a lot. I will upload test clips and look at it and please let me know, how I can solve the problem?

I will appreciate your suggestions, and as promised at the end will share the whole experience so that anyone in the world can go and do it.

Download video (only 1,6 mb quicktime) http://rapidshare.de/files/20500610/3D.mov.html

EDIT: If the question is not clear, the problem is about aligning the cameras in the correct manner. I have tried several things but it just doesn't work. Well I am improving, but I really need to understand in which axis do I need to allign most of all.

Tim Goldman May 15th, 2006 07:01 AM

Hey, good job, looks nice to me.
But heres an idea maybe...could you use like a focal point like lets say painted line on the wall, then use some yarn or string to "map" out the angle and such, sorta use a guide rail to align the cameras. I'm sure this could be solved with math, but I'm an art major, so I don'tknow math.
Maybe you need mounts that are measured of in degrees, then turn each mouth X number of degrees as you go down the rig?

But seriously, it looks good and i think it passes fast enough so that any miss alignment is not to noticable.

(tagged on re edit)

I actually know a bit about 3-d. So let me clear up a few things about 3-d software. Motion capture is usually something you do that involves a rig and special software and maybe even ping pong balls. Rotoscope is where you use pre-exsisting images to figre out motion. (like what bakshi did in wizard or lord of the rings or what their doing in a scanner darkly)

You can scan 2-d images into a 3-d file, but the results are not somehting you'd really want to have to work with. Usually you'd have some animator sit down and re model the scene from refrence photos and useing known distances.
This also depends on the effect you want. Doing this in 3-d, liek say with a 3-d package like maya would be a fairly easy taks, but I actually like the way it looks now, makeing a leap to a 3-d enviroment wold be sorta a shame.
I also don't think it needs to be morphed really, unless that's somehting the client demands. It's cool the way it is!

Cole McDonald May 15th, 2006 07:07 AM

how are you viewing the image you are lining up? If you have an lcd, you can use saranwrap and a marker to mark a point you align on each cam.

afterwards, use software to do a stabilization.

Wayne Morellini May 15th, 2006 09:29 AM

I do not have time to read the thread again but I think I have the gist of it.

What about a arced flat (ribbon) rail with slot through it on one side, 60 precise mounts to mount the cameras flush on in exactly the same angle each one. The mounts have a mount that slides in the slot with no play, they slide up against each other so the mounts are flush against one another. Because the rail holds the desired curves and the mounts are all the same, they naturally space the cameras and cause the angle of the cameras to follow the curve of the rail and touch flat against each other. The rail could be made of an material that can be tensed to produce a curve or shape, but realistically such curves will tend to be parabolic rather then circular.

The other is to buy something that has holes/mounting points and use those. Some sort of strip/rail might have that (hardware store supplier might be good place to find experimental pieces).

for the cameras that slide through the slot and

Cole McDonald May 15th, 2006 11:44 AM

for stabilization software, shake does a good job ($$$) or cinelerra (free). You could do it manually positioning the frames individually, or slow it down a bit more up front by tweening with a morphing software (plenty of free packages)...I'll try to whip up a quick example from the file you provided...Version tracker has MorphX available for download (free) to play with.

Nick Jushchyshyn May 15th, 2006 12:09 PM

A lot of your "jitter" is coming from color balance inconsistancies from camera to camera. Equalize these and you will be cleaning out a substancial amount of the multicamera artifacts you're experiencing.

To help remove X/Y jitter, us a stationary central target (ping pong ball on a stand), shoot a sequence and then run a 2D stabilization on this in post (After Effects Pro, Nuke, Shake). Then, you can copy the stabilization data to your followup real shots. Note, that the most obvious positioning jitter come from sudden shifts in camera tilt (clockwise, counter-clockwise).

Levan Bakhia May 16th, 2006 02:35 AM


Originally Posted by Nick Jushchyshyn
A lot of your "jitter" is coming from color balance inconsistancies from camera to camera. Equalize these and you will be cleaning out a substancial amount of the multicamera artifacts you're experiencing.

To help remove X/Y jitter, us a stationary central target (ping pong ball on a stand), shoot a sequence and then run a 2D stabilization on this in post (After Effects Pro, Nuke, Shake). Then, you can copy the stabilization data to your followup real shots. Note, that the most obvious positioning jitter come from sudden shifts in camera tilt (clockwise, counter-clockwise).

Yes, you are correct. Even thou, I only read this post today, yesterday after a lot of experimenting I came to the same conclusion. It appeared that the marked center in the camera viefinder doesn't match exactly to the center of the taken picture. So what I did, while aliging cameras to one marked point I then shot the point from all the cameras, and then I removed the mark and did my shots. Then in AE, I have aligned picture to the marked point in the picture and copied the corrected keys to the actuall shots, and the result are great. I never tried to correct the colors, and that is not going to be a problem, for this moment, I just wanted to achieve the stable XYZ movement and I did it, even thou it took almos a week of experimenting. Today I will be doing a first fully corrected shot, and tomorrow will upload so that you can see and comment.

Thanks for the help anyways.

Levan Bakhia May 25th, 2006 11:04 AM

Hi, again. Please help me here again if you have any idea.

So, I did alignemnt thing and the motion I get at the end is smooth and very nice. But what happened to be a problem now is sync. there is a slight difference between times the cameras take pictures. I sync them with 2.5mm jacks set up in parrallel connection. After I didn't get the good sync, I did a test. I aligned 15 cameras to the stopwatch and did the shooting. my stopwatch was as detailed as 1/1000 of a sec. So in some cases all the cameras take the same moment but in some cases there is a difference in 1/100 of a second. I couldn't see the pattern and logic, but it is 50/50 sometimes it is sync and sometimes it is not. I have no idea why. Maybe any of you have an idea? All the parameters are identical in the cameras and are manual. also, there is no pattern in the cameras. I mean, I couldn't single out a camera which has delays, it varies from shot to shot. also, I found that in most cases there are two positions in time, some cameras take one and others take second, so there are no multiple differencies.

So any ideas?

Wayne Morellini May 28th, 2006 11:30 AM

I was hoping somebody else would help you, because I am getting away from the lists for the moment, and I don't really know the answer.

I forget your setup (I haven't read through it for a while) it could be in the timer that generates the signal, it could be in the propagation of the signal, it could even be length of wire (electricity travels ten or 100 times slower then the speed of light normally) but yours changes, so it won;t be that, unless their is a resistance/capacitance problem with wire length that effects the way the trigger circuit responds to it. It could be the trigger to the signal not functioning proper, or normal noise problems in the trigger circuit. It could be that the signal going to all the cameras isn't truly parallel so gets out of sync or that the cameras themselves have some variability in their operation that causes the timing to come in late (or early) likely. But there is always a factor of error (unless a timing circuit is 100% accurate, and I don't think we can do that) but it should be accurate enough to constantly be within a hundredth, thousandth, or millionth of a second.

Glance at it with an expert eye, and test the most likely and the simplest to test, potential problems first. The electrical problems would require electrical equipment to test but it should not take more than a couple of hours to go through them all) and if there is not any obvious causes then it is unlikely to be them, unless you have eliminated the other possibilities (electrical problems can propagate, if the camera timing signal runs sequentially from camera to camera. Contact your camera company to ask expert technical people about internal camera timing problems explaining you have bought all those cameras and it isn't working. I think unless there is something not setup right, it might likely be internal camera timing. If they have a service/technical centre nearby maybe they might like to come and have a look.

Sorry this is not more concise, but it's after 3 am here.

Anyway, I am trying to get away from the forums. Have a look at my DIY projects Digital Cinema camera summary, you might find it interesting for when you finish your current jobs ;).




Levan Bakhia May 28th, 2006 12:59 PM

Wayne, I really appreciate your attention and contribution. I realise that the problem I stated was very hard to solve on a distance. Even thou you there is no real way to know, you have tried to help and I appreciate that. I think I found the cure thou. First, I contacted www.ruffy.com as they also use digital canon cameras and thought they could help. Someone replyed saying that canon d350 is not good enough for the sync and there is no way I could solve the problem. That sounded so unhelpfull. After testing everything that came to my mind I have thought about the mirror. Because shutter is a very accurate mechanism, the error in the shutter was almost excluded from my list of potential problems. But then I remember the mirror. Because mirror has to go up beffor the shutter triggers. And there is no need for accuracy in the mirror, the only thing the camera needs is to know when mirror is up to trigger the shutter, not more than that. So I went into the menu of all the cameras and set the mode where on the first push of the button the mirror goes up and then on the second push of the button the shutter is triggered. ( that is used in marco shootings, so that camera doesn't move during the shot ). All cameras I have aimed to a timer with 1/1000 of a second. Before I set this option every 3rd shot I made had some difference in at least 3-5 cameras, after I turned the option, I have done 20 shots and 19 of them were accurate and syncronized to 1/1000 of a second. I don't know what caused inaccuracy in that one case from the 20, but I thinks that I have solved the problem. I will be doing some test tomorrow, and see the acctual result. Promise to let you know how it goes.

Hope this thread will help anyone in future who will try to do the same as me.

Thanks Wayne.


Wayne Morellini May 28th, 2006 02:29 PM

Sounds like what I thought, you could discuss this with the camera company for a firmware fix and get 20 out of 20 shots in sync. The problem with my last reply was that I was so tired, that it is hard to narrow the analysis.

Did you see the ideas I posted for using multiple still cameras to produce HD video? People sometimes ask about making still digital cameras do HD video, so I thought I would post some fun ideas that they could play with.



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