I am trying to match photo to object by establishing where photo was taken from, also adjusting focal length, an experiment of sorts. as other methods have failed.
No, but if you first place your camera and target (in the Perspective viewport) then type Camera and Show, the camera will show up in the other viewports. You can then move the camera’s target control point (along with the cone if you wish) as you want in the Top or other ortho viewports and the Perspective view will change accordingly.
Hi, got it
Did that then in top view with the control points of the ends of my vanishing lines selected along with the C cone and camera cone tip, I used arrow keys and nudged sideways, I then undid the nudges as I also needed the photo to adjust and stay 90 deg to the centre line C to T, so will opt for rotate about the target cone instead, I see though that undoing nudge using multiple undo doesnt see the end of the camera cone also move back to where the C was before nudging it.
Why didnt edit undo also undo the camera movement ?