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Author Topic: Building a 39 camera full body rig  (Read 21562 times)

Lambo

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Re: Building a 39 camera full body rig
« Reply #15 on: August 15, 2014, 12:02:56 AM »
Yes I am also using all different focal lengths in 60 cameras and I still get pretty nice results. I know it could be better but it seems Photoscan does a great job compensating there.
I work on an oval shape area that is around 2.4 m by 3m that's why I need all kinds of focal lengths.
I use F11 that seems to be the best in my case but that varies depending on many variables like for example the amount of light and you seem to have more light than me. I only have 3 flashes.
Leo

ttoke

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Re: Building a 39 camera full body rig
« Reply #16 on: August 15, 2014, 10:11:06 AM »
Sounds good! Actually we bought even more lightning - now we have 10 softboxes with 120w continuous lightning. If we were smarter before, would've used flashes, too. :)

One more question:
Do You guys mask all the pictures manually or does automatic masking work well for you? We have tried automatic masking, but we haven't got any decent results yet. It seems that there is a small movement between two pictures (with an object and without), probably caused by 4 DSLR cameras taking a picture together on a cheap lightning stand.. Also, auto focus is also a problem (the cameras focus on the background on the "empty" picture).

Is it possible to get decent results without masking? We have no luck so far.. usually PS mixes up the back and the front end of an object and creates a very "interesting" object..

Thanks for everyone participating in this thread, you are being very helpful!
« Last Edit: August 15, 2014, 10:22:39 AM by ttoke »

meshmixup

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Re: Building a 39 camera full body rig
« Reply #17 on: August 15, 2014, 10:31:23 AM »
Hi there,

My cameras are not mounted on permanent structure so they can have some displacement after few photo session. One of the solution is to take a set of background photos after/before every capture session. Try to link up the stand can also help to stable your camera. :)

If you have a lot of objects in the background, I am afraid you have to mask it out. I am using white background so I can get photo aligned with /without masking usually. But if someone is wearing white shirt, my nightmare comes.  Lambo knows it ;D

ttoke

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Re: Building a 39 camera full body rig
« Reply #18 on: August 15, 2014, 10:54:17 AM »
Haha, I imagine.

As we are planning to scan brides with white dresses, white background is probably not best for us. What about green? :)

meshmixup

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Re: Building a 39 camera full body rig
« Reply #19 on: August 15, 2014, 12:15:25 PM »
I did not try different background colors, but I think it will do and you may need to tune up the lighting

Digitage

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Re: Building a 39 camera full body rig
« Reply #20 on: August 15, 2014, 08:23:08 PM »

1) Is there a "perfect" focal lenght? Should we take pictures as big as possible or rather zoom the cameras in and try to make 3 pictures (every angle) of different parts + one big "general" picture?


Regarding focal lenght, from my experience there is a balance to find. Basically, when you zoom in a lot, you get more useful data from your model in the picture frame, but you also weaken the robustness of the camera positionning in the first step of your photoscan process, and if your model is not standing in the middle of your rig and your zoom level is important, you risk shooting halfway out...

Lambo

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Re: Building a 39 camera full body rig
« Reply #21 on: August 15, 2014, 09:56:20 PM »
Yes, I know about white dresses! It becomes a nightmare as meshmixup says :) But if the white dress has lots of material texture like stitching or small holes, etc. it helps a lot.
I dont think I would recommend green background since any color close to the subjects bleeds out and the dresses will come out with a slight green tint unless you have the background pretty far from them.
At least that is my experience, I don't know if anyone is using a colored background successfully?
I would guess a possibility is to have a mid grey background?
Also very important, try to go away from auto focus. It is not as important in a constant light situation as yours compared to the flashes but still you can get a few cameras that didn't focus correctly on each session and you will loose important info for the PS process.
You should get someone with nice easy to focus clothes (jeans for example) in the center of the shooting  and manually (or automatically) focus all the cameras. When you are sure all of them are well focused (you should zoom in at least 200% to verify) then you turn them to manual focus and leave them that way.
The masking can be tuned per chunk or per photo if you want. Just use the tolerance slider on the import masks window before applying the mask and test a few different settings until you get the best possible one. After that you might have to do some manual tweaks on each photo anyway.
Leo

ttoke

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Re: Building a 39 camera full body rig
« Reply #22 on: August 18, 2014, 02:25:55 PM »
Thank you very much! We will try different solutions and let you know.  ;)

barkerjs

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Re: Building a 39 camera full body rig
« Reply #23 on: September 04, 2014, 05:39:15 PM »
I'm curious as to what cameras people use for these set ups.  Anyone willing to share their experiences?

meshmixup

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Re: Building a 39 camera full body rig
« Reply #24 on: September 05, 2014, 05:36:59 AM »
Hi, I am using a mix of canon DSLR, 550d, 100d. You may find others are using D3200, 5D markIII or even  raspberry pi. :)

Lambo

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Re: Building a 39 camera full body rig
« Reply #25 on: September 05, 2014, 08:29:44 AM »
I am using all Nikon D5100's.

ttoke

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Re: Building a 39 camera full body rig
« Reply #26 on: September 05, 2014, 12:33:37 PM »
We are finally getting decent and continuous results with our 49 camera rig. :)

The problem is USB - we constantly get about 45-47 pictures of 49, some of them get lost on the way to the computer. We use both USB 2.0 and 3.0 hubs, but bigger distances (3m) are covered with USB 3.0.
Barkerjs - we use Canon 1200D and 1100D.

barkerjs

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Re: Building a 39 camera full body rig
« Reply #27 on: September 05, 2014, 06:18:41 PM »
That's a lot of money for cameras!  I wonder what kind of results you would get from an array of $50-$100 point and shoot cameras?  I saw the Pi array with those cameras, and that quality seems like it's okay for 3d printing at least.

Lambo

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Re: Building a 39 camera full body rig
« Reply #28 on: September 05, 2014, 11:02:51 PM »
If all you are going to do is miniature 3D replicas (no more than 6 inches height) then you can get away with the smaller resolution and quality cameras.
If you are going to do bigger bodies (8 inches or more) or head scans, or some game assets for example, then I dont think those cameras will cut it.
Leo

barkerjs

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Re: Building a 39 camera full body rig
« Reply #29 on: September 08, 2014, 12:18:36 AM »
Interesting.  If I'm doing a full body scan, I'm willing to bet that it's still better than using a Sense scanner or Kinect.  I'm not creating any game assets, just models to display online and to 3d print in color.  But I'm intrigued by the idea, and if the cheap cameras do well, I might be able to step up to nicer DSLR cameras in the future.