Scanning people: Tips needed

[Mark Florquin]

I'm trying to improve on scanning people. It's hard because they move slightly due to breathing during capturing. However I found that if the model lies down, these movements can be minimized.

Has anyone worked with multiple simultaneously triggering camera's? SLR's (best quality) are expensive . However, I think this solution solves the movement problem during capturing entirely.

What do you think? Share your tips...

[FoodMan]

pretty cool...

well yes multi cam is the way to go I think.. look here..

http://www.agisoft.ru/forum/index.php?topic=378.0

[akemono]

Hi Mark,

I think your model looks good, and i don't just mean the woman in the pictures Only thing that stuck me was the lack of high resolution textures. That can help tremendously in giving a more realistic feel to your work.

As for your problem with the subject moving, you can try and setup a kind of dome with a few dslr's equipped with wide-angle lenses to cover as much area without to many camera's. Still this setup would cost quite some money but that is probably the best way to go if you want to capture your model in one go. As for your problem with simultaneously triggering all those camera's, depending on the type of camera, you can get a Infra red remote that will (probably) trigger all the camera's at once.

If you want  to discuss it further or need some other help, you can send me a mail.

Best,
Mike

[Mark Florquin]

Thanks Foodman. I've tried using as few viewpoints around an object as possible for Agisoft to be able to recognize the camera's (I'm using a Nikon D700 with wide angle lens). 12 Is the absolute minimum. The beatle on the agisoft product page http://www.agisoft.ru/products/photoscan/standard/ was shot on a turntable in 24 captures, two rows. I'm thinking of writing a tutorial on the light setup and lens choice for that case.

Akemono, The PDF in the blogpost is only 2048*. Settings for creating texture: Generic Average. Mosaic results in better detail locally, but overall it's inferior to the average setting. I get a lot of artifacts. Any idea's on how to overcome this? Perhaps using single photo and manually composing a texture map?

Anyway, let me know if you have any ideas. Thanks for your dome-tip by the way!

[FoodMan]

hey yes the beetle is really nice.. please write a tut if you got some time.. that would be very nice..

f/

[FoodMan]

btw.. if you're going to use multi canon cams.. this will trigger all at once..

http://www.bhphotovideo.com/c/product/690443-REG/Pearstone_RW_C2_RW_C2_FreeWave_Wireless_Remote.html

[Mark Florquin]

Foodman, thanks for the link! That is a nice solution. Only afterwards, you have to download the photo's from each camera manually.  But totally worth it!

[Infinite]

Really cool results! thanks for sharing.

It's tricky trying to build a multi-camera rig that can capture any kind of pose volume, so this handheld solution is ideal for people lying down or sitting.

The problems are in the focusing, triggering and exposure settings (minimizing DOF also). Capturing a single moment in time from multiple cameras is very hard to do, consistently! as you need multiple PC's networked and lots of patience.

I'm currently finalizing a full body rig at the moment



Did you think of trying a fig rig with a stereo pair of cameras? tethered and triggered by a PocketWizard mounted on the Figrig? This can also be quite useful.

[Mark Florquin]

Hi Infinite,

The problem with a turntable: you can't capture action! Which cameras are you using? Are there maybe camera's without preview screens and excess funtionality one can buy cheaply?

Anyways, keep up the good work!

[hsmith]

Hey Lee,

I hope this isn't off topic, and if it is, I apologize in advance.

I remember your excellent work on another forum related to scanning human subjects.  The software relied on stereo pairs and projecting a noise pattern. (I won't mention it here).  Would you please give me an idea why you've changed to agisoft photoscan? 

Harold

[Mark Florquin]

Me too, I was wondering about the benefits of using stereo paired camera's. Can you post examples with / without?

[hsmith]

Lee,

I just found your own website and, after reading the most recent posts, I believe I could predict your answer.
It's amazing how many more polygons the agisoft program generates, and how greater the resolution it produces.
Great work!

Harold

[Infinite]

Hey Mark,

Great to see cool scans! I always get a buzz when I see cool human scans in colour! It would be good to see a grab of the grey scale mesh, to see how the scan came out. The colour looks great.

Mark and Harold: I still use Stereo pairs, with a combination of other Camera positions. I use Agisoft simply because of it's user friendly graphical interface, python support and other features. Plus the results are "volumetric" and not just from a single calibrated pair of Cameras (oh and the fact you don't need waste time calibrating) The results you can get are really incredible. You just need well placed, well lit and well focused images.

Hoping to see more Humans scans here!

Lee

[Infinite]

Which cameras are you using? Are there maybe camera's without preview screens and excess funtionality one can buy cheaply?

I use Canon 550D's because of the great support Breeze Software offers for multi-camera tethering. Not sure what else you can use. Sony's 24fps new Cameras look interesting, Pentax? Nikon? but all come with limited multi-camera support. Unless you can get some one to write something and of course the Cameras really need triggering and data input ports.

[hsmith]

Mark,
I've never used the CHDK hacks for Canon cameras, so I can't say how well they work.  But you might be interested in trying this strategy for some lower cost cameras:

http://chdk.wikia.com/wiki/CHDK

Best of luck

Harold
PS Lee, thanks for the response!