Hello,
I have a few questions regarding the combination of laser scan and pictures.
My first question is how to determine how many control points are needed and how accurate the control points needs to be defined. I have done a few trials, but up till now none of them succeeded…
Can you combine a Laser scan in black and white with a color picture without control points (if there is enough overlap between them)
If a laser scan and pictures are combined with the aid of control points, is there an extra optimization step, which takes also the actual points of both into account to make sure the laser scan and pictures fit well together…
Thanks in advance,
Tom Traen
Hi Tom
If laser scans are not with color (intensity values ), you will get into problems, as intensity values are not like RGB-grayscale conversion. So it looks quite different in laser scans and in images. That is why they cannot be aligned without CPs/GCPs.
Regarding CPs/GCPs, you need to use so many as needed, the number always depends on a project, so sometimes 3 CPs ( 6+ images per CP ) and sometimes 50+ CPs/GCPs need to be used…
Oh ok, now I understand the problem.
More than 50 CP is of course not usefull for an efficient workflow. What would you advise? Use a laser scan in color?
The problem with our laser scanner is that it does not have an HDR camera, which meant the color is not always good. Even bad color is better than intensity values? What advise could you give to use as less CP as possible? And my final question is it possible at the end to color the grayscale laser scan with the pictures?
Kindly regards,
Tom Traen
Hi Tom
Yes, use color even though there is not a HDR camera. Get good resolution on scans to get it easily together…
But depending on a project, not every single scan must be with color…