Hi Götz,
Thanks for the reply.
I enter 50 units as the defined distance.
It’s quite strange, it seems when i update the alignment it,
1)-Sets the calculated distance to zero. Then because of this it distorts the camera positions until the two points do have zero distance between them. End result being it pulls all the cameras to the single point.
2)-Tells me my control points have a p value of 100px. Which I’m assuming it clips at 100. Before the update alignment they were less than 1px.
I re-did the whole model a few times. Setting the control points on the same scale object but from a different selection of photos. Eventually it just worked and scaled everything properly.