Waves in scanns

[Carl_3D_WOOD]

I'm having trouble with waves, slicing, patterns in my scans I have tried all the recommended fixes I have found. Any ideas? I'm using a new standard David SLS-3 with V5.1 software and a second David camera. I'm new to David and currently use photogrammetry and IR rangefinder systems to do my captures.

To solve the wave issue I have tried 3 different computers, 2 different projectors, tried all combinations of projector frequency, camera frame rates, camera exposure, have no problems with calibration.

The scans look mostly fine with the texture on this phenomenon is seems more pronounced on curved objects and sometimes at certain light levels.

 thanks, any help greatly appreciated

Carl Geiger

[drndadoo]

Are you scanning in a dark room? If no, please try. Turn all lights off and avoid sunlight.

[Silver_Ghost]

Here in some posts there were mentioned that there are no lines in scans with the original david/hp hardware. It is not so at all: look to the picture from the HP 3d Scan product page:

I've marked lines here.

[WaldoPepper99]

Hi,

are the sine waves in the scanner control window topped off?

May be you can make a screenshot of that particular window and post it here.

[Carl_3D_WOOD]

I do my 3D scans in a dark room but have tried many different lighting conditions.  

i have tried different exposures and video clipping is not a contributing factor.

I have tried many different advanced settings.  

Minwavelength setting is the only one that has any noticable effect on the waves.

Below: Scans, different settings for MinWaveLength LtoR 12, 24, 48.

very frustrated, using this scanner requires too much work to clean up the scans to be useful for my needs.  Wish it worked because photogramity has many challenges as well.

carl

[Curiousjeff]

There are numerous threads in the old David forum devoted to waves in scans.

Have a look. It does unfortunately take a lot of time to go through it.

To sum up some of my experience:

Start with 60hz on projector, 1/60 on camera, then fine tune:

Adjust frequency on camera to have the less possible waves moving through the screen in live view.

Adjust frequency of projector using graphic card if possible to better fine tune the adjustment.

If using Acer K132 (or 135), do not use at full brightness (my personal experience).

Start by scanning still items with a mat surface

You will see incredible results on the old forum for many users.

Jeff

P.S. Some waves will be removed by the fusion step

[drndadoo]

Hi Carl,

can you please try to make a small experiment. Uninstall gfx card driver and use windows generic driver for your gfx card.

[Stive_rad]

about wavy scan: as you scanned a human face, I can guess the object (face) is not completely static and stable during scanning process.

if you have this problem on other object, try other combination of resolution for your camera and projector. For first step, set your cam to highest res and change your projector resolution. also frequency of projector and cam should set to 1/60 sec.

in first topic you talk about "photogrammetry and IR rangefinder systems to do my captures", Can I know more about these systems?

[Carl_3D_WOOD]

i have waves even with static items such as the soccer ball example.  camera and projector are both at 1/60 plus i have tried many other combinations.     i have tried various de-focus of projector but not much defocus of camera.     Thanks for the advice, i will try defocus of camera.

Carl

  photogrammetry: Many pictures from different angles, 123d catch, Autodesk remake, Agisoft PhotoScan

IR rangefinder: such as Occipital Structure Sensor

[Stive_rad]

Hi

So try various brightness and  contrast ratio. what about lens? wide angle??

send a screnshot of your software window.