Problem with taking the right photos for reconstrucion

[szafir51]

Hello,

I'm trying to make 3d scan of RC car. I've taken 50 photos of car chassis using fixed camera position and rotating object on a turntable.
Unfortunately Zephyr can fail with reconstruction:

Reconstruction Failed!
Well, this is embarrassing.
Something went wrong.
Please run processing again.
Try to make more photos or to change reconstruction parameters.

I'm using Micro FourThirds Olympus E-M10 camera with 40mm focal lenght (35mm eqv) and external flash.
Could you tell me what am I doing wrong or how I should improve my photo-set?
I know that black uniform surfaces are tough for 3d photogrammetry software but the same situation is with the car body whitch is colour and well textured.

You can find my data-set here:

http://drive.google.com/drive/folders/17iMfS5PWgu2FQiit_qQ_dqaeevfJHJ-8?usp=sharing

Regards

[Andrea Alessi]

Hi szafir,

1. in the first set (the black car) i would also mask the images, as there aren't many features on the car itself, so zephyr is also picking up features from the wall. Luckily, since there is a very high contrast you can easily make masks in few clicks, in masquerade use the red brush on the center of the subject, use the blue brush on the wall, and use the autocompute function.

2. the second set is harder, as many images are out of focus ( 20171130-PB300671.jpg ) and other are underexposed. You should also mask this one due to the reflections on the table. I'm not sure how well this dataset would perform however, as the images aren't very sharp and the subject isn't very textured.

3. the third one is also very hard, as it is not feature rich enough, glossy, and there are few photos. As a workaround, you should try and dirty the surface, use a pico projector or maybe try with a newspaper below it to help the first phase. Anyways, you should take more pictures.

When dealing with close range, i also suggest you use a different aperture, so that everything is in focus. Also avoid flash, try to use diffused lighting.

You can find some tips on photography and an example of the projector trick on this videotutorial https://www.youtube.com/watch?v=E06kgYBftak

Unfortunately i can not process them now as all our workstations are busy, but i'll try to do that in the next few days, but i would expect Zephyr to discard most images

[szafir51]

Thank you for your valuable suggestions. I'll try to prepare new set of photos in daylight. I'll also paint the car body with different colours.