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Author Topic: Turntable vs rotating camera  (Read 9840 times)

lamakina

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Turntable vs rotating camera
« on: January 23, 2018, 12:39:04 AM »
I'd like to find out which is the better option for a simple 3 SLR setup. I'm trying to decide between two setups: rotating cameras vs rotating subject.

A: 3 static cameras + subject on a rotating turntable + green background for easy masking (I heard/read white or black would not be ideal for a background)
or
B: The subject is static, 3 cameras rotate around the subject using a rotating rig (no special background, just the room we're in)

Which setup is most likely to give the best scan results? I have a suspicion that B (rotating cameras) would work best, but I'm kind of hoping someone would prove me wrong. (I'd prefer a turntable)

In the end I'd like to build an Arduino driven setup which controls rotating speed and triggers the cameras at 10° intervals.
This would work with either setup: static camera or static subject. So now I'm trying to figure out which route to go...

What would be your advice? Is there a clear winner, or are results very similar?
Any help or advice would be greatly appreciated!
« Last Edit: January 23, 2018, 01:41:45 AM by lamakina »

SAV

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Re: Turntable vs rotating camera
« Reply #1 on: January 30, 2018, 06:27:25 AM »
Hi lamakina,

I would go for option A, mainly because you can then automatically mask the background, which will give you cleaner reconstruction results. 

You should also think about lighting. Use LED light strips with a high CRI value.

Regards,
SAV
« Last Edit: January 30, 2018, 11:13:49 AM by SAV »

lamakina

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Re: Turntable vs rotating camera
« Reply #2 on: February 26, 2018, 12:49:19 PM »
Thank you for your reply. Is the high CRI value of the led strips important to get a good and correctly coloured texture layer, or does that influence the 3D shape also? Because for my application I don't need a texture layer. The results will be used for 3D printing only.

SAV

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Re: Turntable vs rotating camera
« Reply #3 on: February 27, 2018, 02:59:23 AM »
Hi Iamakina,

CRI is a measure of how accurately a light source illuminates an objects' true colors. Not really important in your case if you don't care about the texture.

Regards,
SAV

Mixers

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Re: Turntable vs rotating camera
« Reply #4 on: May 14, 2018, 05:41:30 PM »
If you look at profession solutions "out of the box" they use a set of cameras moving around the object. For example a Shapify full body scanner. They also use light sources which move with the cameras. I suppose it's for the same lighting from every angle.

But such device is too huge for me. And too expensive)
For myself I found a solution when the object is on turntable and the 3d scanner (not just a camera) moves up and down  and changes the angle up and down so it can capture all the details.  I use a scanner from that Shapify manufacturer and quality is much better than with Shapify or cameras and photogrammetry.