Focal lenght

[working_guy]

Hello to all.
I'm New where and I'm starting with Agisoft/Metashape.

I work with aereal photogrammetry, and I have a doubt.

When I insert photos the app view the câmera and the focal length (something like 2311.****) after align the photos sometimes the focal length change and anothers don't.

It's normal the focal lenght changed in adjusted settings?.

Thanks in advanced.

Hugo Ricardo Silva

[working_guy]

nobody?

[Alexey Pasumansky]

Hello Hugo,

The Initial focal length value that you see in the Camera Calibration dialog is calculated according to the image meta data (basing on the EXIF focal length value and sensor pixel size). During the alignment Metashape is performing autocalibration procedure and the calibration parameters / distortion coefficients are refined. So some deviations from the Initial values are expected.

In cases when you do not see any changes applied to focal length (and other parameters), I assume, you have Adaptive Camera Model Fitting option enabled in the Align Photos dialog. This option allows the application to decide automatically, which coefficients should be refined.

[working_guy]

Thanks Alexey

I see what you said.

For now I allways select the Camera Model Fitting option in the Align Photos, and the Focal lenght changes.