[ptx] Need clarification of autopan -> hugin -> enblend workflow

[John Bäckstrand]

Douglass Turner wrote:

>Hello,
>
>I'm an ole panorama hand but new to autopano+hugin+enblend. Could
>someone please clarify the workflow from autopano to hugin to enblend?
>I was able to have autopano successfully generate a project file for
>hugin. When I loaded the project I was unclear on what to do next.
>
>If someone could quickly walk me through the steps that would be excellent.
>
>Thanks,
>Douglass Turner
>voice/sms: +354 895 5077
>
>
>  
>
Im certainly no expert my self, but I can try to explain what I do, I 
wont promise this is the best way to go:

1) Create panoramas in a directory with autopano, though this I do only 
if Ive got multiple panoramas, only happened once, otherwise I just open 
the images in Hugin and select them all then press "Create Ctrl Points" 
which will invoke Autopano for you.

2) Choose an anchor image, but I dont always do this. Some image in the 
center of the panorama should be fine.

2) Now you should have a bunch of images open, and clicking the "Control 
Points" tab and choosing two overlapping pictures for left/right should 
show where the control points are. Ive never seen a false positive with 
Autopano so I never check them, but you might want to. I usually add 
some points though, the points from Autopano seem to clump toghether, 
and I feel it lowers the reliability of the optimization, so I usually 
add points to towards the edges of the pictures when they dont stitch up 
nicely. Im not sure this helps, Ive gotten no clear evidence it does.

3) Go to the "Optimizer" tab and first choose "Positions (pairwise 
optim. starting from anchor)" and optimize with that by clicking 
"Optimize now!". Then I usually do one or more of the following, in this 
approx order:
   
    Custom optim. with everything deselected except view, seldomly used, 
usually results in a very slight change in hfov.
    Custom optim. with everything deselected except dist a, barrel and 
dist c.
    Custom optim. with all of yaw, pitch and roll selected, except for 
anchor image, and dist a, barrel and dist c selected.
    Optimize everything. I dont do this very often, view almost always 
gets crazy.

4) I (cautiosly) click preview at this point. If it looks OK, and often 
even when it doesnt, I do a few try-stitches from the "Stitcher" tab, 
closing the preview first, since I get a lot of crashes from it:
   
    Click Calulcate Field of View (not always necessary)
    Calulcate Optimal Pixel Size, then size down to reduce stitch-time 
for previews.
    Choose image format and stitching engine, I usually go for multiple 
TIFF and nona, otherwise TIFF and check the enblend-checkbox.

5) Run enblend on the images created in step 4. I do this separately and 
from the command line since Ive been having problems with enblend dying 
in the middle when being run from hugin, out-of-memory error maybe? I 
dont know. Running separately is fine though.

---
John Bäckstrand