Good points :-)
Can you explain the comment
"Three ping pong ball's, or similar, will make rotate alignment's much easier in post-processing."
in more detail please? Sounds useful.
Your semi-circular rig will have a focus point common to all the cameras in the middle of all cameras, H and V, field's of view.
If you place a (single) ball alignment target at that point you can then adjust the, course, x-y camera alignment's.
The, fine, x-y (and r) camera alignment's are then done using Align_Image_Stack, and these values are re-used when
attempting to create the gif's or video's.
For the rotate camera alignment requires a vertical line through the focus point common to all the cameras.
To obtain the best and most accurate rotate camera alignment the vertical line should be as long as possible.
While maintaining the focus common to the cameras H and V, field's of view's.
An easy way to achieve this is with two additional ball targets.
i.e. Ping-Pong, tennis, golf balls (or even a trig-ball anchor-ball as by surveyors and sailors).
Why:-
Imagine a spinning top, at the focus point common to all the cameras.
Initially the tops axis is perfectly aligned as above. Then at the very end the top no longer maintains this perfect alignment.
That is similar to what will happen if the x-y or rotate camera alignment drift etc. i.e. a "Fast Jitter" and/or a "Slow Wobble"
Both types can become very annoying.
If you then have an additional overhead camera to capture a common "Plan View" you might also
be able to use PhotoScan software to then create a PhotoScan wire frame 3D model. That may be useful in some
circumstances. i.e. Camera Locations etc. Note that horizontal x-y views have more
"PhotoScan-Data" and vertical plan view will have less "PhotoScanData". i.e. the H and V have different resolution's.
Also note that there will be an optimum "Subject" location i.e. at or near-by to the focus point of the cameras, H and V, field's of view.
So some times all the cameras might be orientated in portrait or other times in landscape.
H-H
