Manual camera position?

[fermanrique]

Hi,

I have spent a couple of weeks using PhotoScan but there are a couple of thinks that don't seem to be possible and I think that they would be very useful. Specifically, is there any way that I can manually position cameras that are not correctly aligned by PS? and, is  there any way to manually set points (or edit existing matching points) to improve results?

The only way that I've found to modify camera positions is to export cameras, manually modify the XML and then import them again but that is too complicated.

I hope that I'm missing something and there is a way to achieve what I'm trying to do (?)

[Alexey Pasumansky]

Hello fermanrique,

You can use markers as valid matches to help the alignment. The procedure is described on the 9th page of PhotoScan Pro manual.
Following this scenario you need to reset the alignment to incorrectly aligned cameras, place at least four markers on each of such photos (each marker should have at least two projections on correctly aligned images), then select these cameras and perform Align Selected operation.

[fermanrique]

Hi Alexey,
Thanks for your quick response but I use PS standard (not pro). Is there anyway to be able to achieve something similar  in this version of the software?

[Alexey Pasumansky]

Hello fermanrique,

In Standard edition you can only try to use Align Selected option for NA cameras, sometimes it could help to get cameras into correct positions.

To use XML file import you need to know exact camera positions and rotation.

[fermanrique]

Thanks for your answer.
It seems that I may have to consider the Pro version....

[Alexey Pasumansky]

Hello fermanrique,

And what type of object/scene do you reconstruct commonly? Probably, you can improve the capturing scenario and/or shooting conditions to improve the result of alignment.

[Heinrich]

Alexey,
I use the Pro version, and have in some cases added dozens of markers. To no avail, if the subject I intend to model has repetitive features (architecture), as it seems the false matches outweigh the manually places ones. I even get cameras under the ground etc., and often no trick works to fix them.

Manual placing would be really neat, as I can measure relative camera position very well using lasers, as well as align my camera perfectly.

Alternatively, or additionally: an option that tells Photoscan to ignore ANY points found EXCEPT the markers! That should work, too, with fewer markers (4 minimum). However, I do not know how well dense point cloud generation would then work, as there would still be false matches for that step.