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Author Topic: Building mesh of a Face - Poor Quality  (Read 11127 times)

techead

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Building mesh of a Face - Poor Quality
« on: December 08, 2016, 11:31:45 AM »
Hi all

I am following this Youtube tutorial where he goes step-by-step and he gets some amazing results.

https://www.youtube.com/watch?v=GEsRcFQ1_H8&t=622s

I'm literally doing the exact same thing, except I have MORE photos, and yet in the step after I build the Dense Cloud, I am building the Mesh and I am getting very poor quality.

I am trying to export this mesh to a STL file to print, but the face is not smooth at all like in the tutorial.

Any ideas what I am doing wrong?

Lapin

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Re: Building mesh of a Face - Poor Quality
« Reply #1 on: December 08, 2016, 02:28:26 PM »
techead, can we see your photos? Probably the roughness of the mesh is the result of noise in the photos.

Cheers,
Steve

techead

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Re: Building mesh of a Face - Poor Quality
« Reply #2 on: December 08, 2016, 02:30:43 PM »
techead, can we see your photos? Probably the roughness of the mesh is the result of noise in the photos.

Cheers,
Steve

unfortunately I dont have access to them here at the office, but I can assure you there is no noise on the photo's at all


techead

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Re: Building mesh of a Face - Poor Quality
« Reply #3 on: December 08, 2016, 02:34:01 PM »
there is one thing that I might be doing wrong...

I require an STL file to import into CURA.

I am creating a MESH in Agisoft Photoscan, and it is at THIS point where I am getting poor quality. Do I need to still BUILD TEXTURE and then export the STL after that stage?

James

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Re: Building mesh of a Face - Poor Quality
« Reply #4 on: December 08, 2016, 02:42:38 PM »
Children have much smoother skin with less detail/information than the adult shown in the youtube video, which is probably problem #1, and secondly children are probably less capable of staying still long enough if you are using a single camera. Any other problems will be in your photos, which are yet to be seen.

From my modest experience, noise quantity really depends on the subject and its skin quality.
With children with very smooth and spotless skins, the result is very noisy with big holes in the point cloud, while with old skin full of moles and wrikles the result are much more precise.

techead

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Re: Building mesh of a Face - Poor Quality
« Reply #5 on: December 08, 2016, 03:13:07 PM »
https://www.youtube.com/watch?v=EELoTXJxoiA&t=697s

another example of a very simple import process and getting almost flawless smooth even on the dense cloud stage!!!

check at about 12:00 in the video

James

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Re: Building mesh of a Face - Poor Quality
« Reply #6 on: December 08, 2016, 04:19:43 PM »
The more flawless and featureless the surface the noisier the result will be.

The latest video you posted was of a scan of a 1st century bust of heracles which is perfect for scanning due to all the imperfections in the surface.

The first video was of a stubbly adult with well aged skin, but it looks like you are trying to scan a child with no stubble or deteriorating stonework and that is your main problem, i promise i'm not making it up!
« Last Edit: December 08, 2016, 04:21:18 PM by James »

techead

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Re: Building mesh of a Face - Poor Quality
« Reply #7 on: December 08, 2016, 04:27:34 PM »
ok thanks for the feedback, and I definitely believe you, I just dont understand why.

I used some photos that I took of my wife, and the same story. I cant help but wonder if the settings that I am using are not also playing a part in this??

Lapin

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Re: Building mesh of a Face - Poor Quality
« Reply #8 on: December 08, 2016, 07:30:31 PM »
It is difficult to guess. Pour photos for sharing and together we will test. )

badger

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Re: Building mesh of a Face - Poor Quality
« Reply #9 on: December 12, 2016, 01:42:53 AM »
Hi all

I am following this Youtube tutorial where he goes step-by-step and he gets some amazing results.

https://www.youtube.com/watch?v=GEsRcFQ1_H8&t=622s

I'm literally doing the exact same thing, except I have MORE photos, and yet in the step after I build the Dense Cloud, I am building the Mesh and I am getting very poor quality.

I am trying to export this mesh to a STL file to print, but the face is not smooth at all like in the tutorial.

Any ideas what I am doing wrong?

How long did it take you to shoot all the photos ? The boy should be frozen during the shooting. Unless you use a multicamera rig I think it's close to impossible that a boy does not move for the entire time needed.

techead

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Re: Building mesh of a Face - Poor Quality
« Reply #10 on: December 12, 2016, 11:23:45 AM »
About 10 min to shoot all the photos. Worth pointing out that the light wasnt great and I wasnt shooting using optimal camera settings.

I did some more photo's on the weekend, this time outside (not direct sunlight) and using AP priority on the camera, used 11. The light was much better, and the result was MUCH better.

So this whole exercise is definitely GOING to work, it is just a case of getting the right light, shooting good photos with a high MegaPixel, low ISO, and in RAW format.

We are going to get this right.... :) It is just going to take a lot of practice and work!


Hi all

I am following this Youtube tutorial where he goes step-by-step and he gets some amazing results.

https://www.youtube.com/watch?v=GEsRcFQ1_H8&t=622s

I'm literally doing the exact same thing, except I have MORE photos, and yet in the step after I build the Dense Cloud, I am building the Mesh and I am getting very poor quality.

I am trying to export this mesh to a STL file to print, but the face is not smooth at all like in the tutorial.

Any ideas what I am doing wrong?

How long did it take you to shoot all the photos ? The boy should be frozen during the shooting. Unless you use a multicamera rig I think it's close to impossible that a boy does not move for the entire time needed.


Alexey Pasumansky

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Re: Building mesh of a Face - Poor Quality
« Reply #11 on: December 12, 2016, 11:48:30 AM »
Hello tachead,

Have you seen the video-tutorial by Jeffrey Ian Wilson regarding single camera head scanning?

https://www.youtube.com/watch?v=7z4tYaibuAs
Best regards,
Alexey Pasumansky,
Agisoft LLC

techead

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Re: Building mesh of a Face - Poor Quality
« Reply #12 on: December 12, 2016, 11:54:14 AM »
Wow, that is a long video. Ok, I am going to watch it and provide feedback when I can

Thank you for posting this


Hello tachead,

Have you seen the video-tutorial by Jeffrey Ian Wilson regarding single camera head scanning?

https://www.youtube.com/watch?v=7z4tYaibuAs

Alexey Pasumansky

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Re: Building mesh of a Face - Poor Quality
« Reply #13 on: December 12, 2016, 12:37:09 PM »
It covers several aspects, including shooting process, image pre-processing, processing in PhotoScan, post-processing of the model and texture.
Best regards,
Alexey Pasumansky,
Agisoft LLC

techead

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Re: Building mesh of a Face - Poor Quality
« Reply #14 on: December 14, 2016, 09:59:12 AM »
Ok, I've watched this entire video and I can see there is a lot involved in this.

I do think that most of the videos on Youtube showing people taking photos and making it look easy are actually very misleading.

From what I can see, everything boils down to the quality of the photos. It's really that simple. Getting the correct lighting, correct depth of field, and focus on the focal points rather than getting pretty pictures. In other words, quality > quantity.

In his example he has almost three times as many points compared to a project that I am working on, and I have double the amount of photos.

Oh, and dont underestimate Adobe Lightroom. I ran all my photos through the steps in his video, and the difference it made was incredible.

I could go on and on, but the bottom line is that it's certainly possibly with a single camera. Just takes a lot of practice and patience.