Topics

16

General / Expected stability of camera parameters when using a DSLR + fixed focal lens ?

« on: April 05, 2014, 04:26:36 PM »

My question is about using or not a fixed camera calibration.
I repeatedly use a same camera  (Nikon D5200) with a same single focal lens (50mm)
There is typically 0,5% variatiability in Photoscan estimated focal lenght between independent calibrations on similar scenes. I expect this to come from the calibrating process plus some flexibility in the camera+lens systems.
If for instance the true camera+lens characteristics would be stable within 0,1%, I should probably use camera fixed calibration.

I would like to know
- Is this 0,5% variability in the range of what is expected  (or low or high ?)
- Does someone knows what is the part of variability expected from  the camera+lens characteristics in my case (camera is attached to a monopod; variability over a period of several weeks, with usually mount/dismount of the lens, some change in air temperature, etc ) ?
Thx for any hint

Bruno

17

Bug Reports / Mild filtering filter more than moderate filtering

« on: March 26, 2014, 11:07:53 PM »

I generated a model of a pot containing wheat plants. With the same images I generated point clouds with several accuracy (ultra high, high, medium) and compared between mild and moderate filtering.

I observe consistently that dense points clouds generated with moderate filtering have more points than dense point clouds generated with mild filtering. Moreover these extra points are often artefacts. I expected  the opposite behavior . Is there an explanation?

Attached are capture showing the pont clouds generated with "ultra high" accuracy and mild or moderate filtering.
The yellow margins around the leaves (specially in moderate filtering) are artefact coming from the soil background.  They are more of them in "moderate" than in "mild". You can also see that the sides of the pot, which lacks good texture, have been eliminated with "mild" but not with "moderate" filtering. So I am confused by this.
BTW : what would be the best method to avoid the margins coming from background ?

Bruno

18

Feature Requests / Comparing results obtained with different options

« on: March 22, 2014, 05:40:06 PM »

Hello

I am using photoscan for reconstuction of plants and comparing how various options change the results (which are very nice actually !).
At the moment for storing results , I  create duplicated  chunks containing the same cameras. Also  I cannot reorganize the order of the chunks in the list

It would be great to have facilities for organizing the work space in directories
(directories of chunk, and within a chunk, directories for storing several dense clouds or models, etc.

Bruno

19

Feature Requests / camera tools

« on: March 21, 2014, 06:18:35 PM »

I frequently use a large number of cameras, for which I have not full control of the position. Then I must delete or disable redundant cameras based on image quality.

It would be very usefull to be able to select a camera based on their position on the model window (ie right click on the blue rectangle), get the information about camera (eg image quality, etc) and diseable or delete that camera.

Also
it would be nice that user can define (in preference) the size of the rectangle showing a camera.
it would be nice that the photos pane contains columns showing camera position.

20

Bug Reports / no pointcloud is produced when using openCL

« on: February 11, 2014, 08:26:00 PM »

Hello

Photoscan 1.01 fails to produce a pointcloud when using openCL. According to the logfile, it seems as the process does not even start. Can you help ?

I attached two logfiles for the same dataset, with and without enabling openCL.


I am using the following equipment

HP Z800 64G de RAM, bi-proc Xeon E5330 2.4GHz (2x8 cores)
   OS = CentOS 6.5
Graphic card : NVIDIA GTX 690 4G RAM
   driver : NVIDIA-Linux-x86_64-304.119
When enabling Open CL I disactivate two CPUs

PS This is related to my previous question with using openCL but I just realized that the problem is for producing the pointcloud and not the mesh.

21

Bug Reports / no mesh is produced when using openCL

« on: February 03, 2014, 07:22:14 PM »

Hello

When running Photoscan Pro , the system fails to calculate a mesh when OpenCl is enabled
(programm is stopped somewhere and produce nothing).

Any hint ?

Thanks

Bruno

I am using the following equipment

HP Z800 64G de RAM, bi-proc Xeon E5330 2.4GHz (2x8 cores)
   OS = CentOS 6.5
Graphic card : NVIDIA GTX 690 4G RAM
   driver : NVIDIA-Linux-x86_64-304.119

(When enabling Open CL I disactivate two CPU)