"Optimize cameras" -> results worse than before?!

[ThomasVD]

Hi everyone,

I'm trying to do the 'optimize cameras' step based on the known distance of scale bars, as explained on p35-36 of the Professional Edition user manual: http://www.agisoft.com/pdf/photoscan-pro_1_1_en.pdf. In my project, hundreds of scale bars cover a wreck, and each one is exactly 75cm long.

I placed markers at both ends of these scale bars, selected both markers to make a scale bar, then set each scale bar's distance to .75m. I then clicked 'update' to be able to see what the total error was, and it was quite low at 0.011389. Then I selected all scale bars and clicked 'optimize cameras'. However after optimization the total error has actually increased to 0.029667.

Shouldn't optimization find the best fit between these values and improve my results?
What can I do to actually improve results? Should I change the 'reference settings' or something?

Any help is much appreciated!

[Ant]

Hi ThomasVD,

I also struggle with the scale bar optimization. My errors are the same or even worse after the optimization.

Funny enough I did the same comparison with a previous version of Photoscan Pro (1.0.x) and the optimisation process was giving me smaller errors.

Not sure if there is a bug with version 1.1.

I've also posted a comment about it about a week ago but no one came back to me :-(

Cheers,
Ant