Way to follow with small models?

[zzgus]

Can someone put some light in the way to follow with small models?

At what angle must I take the pictures? perpendicular to the model? or with some inclination?

When trying to take pictures to small models I get a lot of DOF. Will the program work well with this DOF? Is there any trick to take the pictures without too much DOF?

Thankyou
Gus

[janosch1234]

Hi Gus,

DOF is bad in many ways:

- not very much points will be detected in the blurred parts
- the point accuracy is bad
- resulting textures will be blurred.

I would try to avoid DOF by taking the aperture of the objective up to the highest aperture value. You may choose a tripod for this setup too, because the shutter speed times will then be longer too.

If its not possible try to scan focused parts of the model and then you have to join these with chunkalignment or manually in a program like meshlab.

Regards
Jan

[zzgus]

Thankyou Jan but I'm not getting good results.
Perhaps I'm doing something wrong.

Here's an example:

I tried with one Minnie model from my childs.

http://i346.photobucket.com/albums/p433/zzgus/VARIS/M_Picture01.jpg


I made some pictures around the model:

http://i346.photobucket.com/albums/p433/zzgus/VARIS/M_Picture00.jpg


Here you can see the quality (NIKON D90):

http://i346.photobucket.com/albums/p433/zzgus/VARIS/M_Picture02.jpg


Got into PHOTOSCAN and ALIGN PHOTOS. (Accuracy HIGH). I think the result is good:

http://i346.photobucket.com/albums/p433/zzgus/VARIS/M_Picture03.jpg


But once I BUILD GEOMETRY (with highest values), that's what I get:

http://i346.photobucket.com/albums/p433/zzgus/VARIS/M_Picture04.jpg


What am I doing Wrong?
Does someone have some pictures with a good result of a miniature model?

Thankyou
Gus

[GPC]

What ISO are you shooting at.. looks pretty noisy to me. Little plastic models don't have a lot of texture.. that type of smooth painted material with gloss are just bad for reconstruction. All the texture I see in Minnie's face is ISO noise.

I would:

1. Get more light
2. Reduce aperture
3. Zoom in more
4. Reduce ISO

I think you could use more photos too.. some of the rotations seem like pretty big changes.

[Gatto]

Use a tripod, use more depth of field (close the iris), use low ISO as possible, shot in bouncing light zone, no flash, avoid reflecting objects (if the object is reflective, paint it or cover it with talc and remove excess vibrating it) use good macro optics and good reflex, shot with all settings to zero (shotting profiles), use remore shotting or auto timer to avoid vibrations due to the hand.

Small objects is same as big ones, understand that to recognize details 3 shots are needed, spent time with only 3 pics to understand the process.

This one is a small model, please note the texturized print under the object to help program to align pics.



and here the 3d model

http://www.gatto.com/lucio.pdf

Meow