Double exposure stack should warn.

In bug 679092 a user had a nice PANO-head setup where he could take 20 pictures in 18 degree increments.

Of course you want to be sure you didn't miss the first image, so instead of taking 20 pictures you take 21. Then when you want to do HDR, you'll shoot 3 images each. The first and last image end up overlapping enough to be detected as a "stack".

Another reason to have this overlap would be to be sure that you can edit out moving targets. With the normal progress there are only a few seconds between a shot and the next one in the next position. But for the first and last image a 20x longer interval is observed. So taking an extra set allows you to match them appropriately.

The result is that stacks are available: 0-360 degrees inclusive at 18 deg intervals, with two stacks as 0 and 360 overlapping.

This is (was?) not detected and enfuse was ordered to consider it as one stack.

I think that hugin should be able to detect this situation, and create two stacks.

Failing that, it should at least warn when the stacks are of differing height. (stack heigth =3 for positions 18 - 342 degrees, but stackheight = 6 for the stack at 0/360 degrees.

NOT tested on latest hugin.

- To reproduce copy over the first three images of a normal 360 degree pano, and place them at the end and see what happens.