How to improve.

[Jeff Burns]

I have been working with this image for days, but cannot get a clean stitch. I have small misalignments.   When I took the pictures the camera was mounted on a regular ballhead so there is some parallax error. 

Would a different optimization strategy solve the problem? 

Is there a workable post processing strategy to fix the errors?

If I retook the pictures with a fixture that allows the camera to rotate around the zero parallax point, would the problems go away? 

Jeff

[Terry Duell]

Hello Jeff,

On Wed, 23 Dec 2015 09:25:04 +1100, Jeff Burns <je...@burnshome.org> wrote:

>
>
> I have been working with this image for days, but cannot get a clean
> stitch. I have small misalignments. When I took the pictures the camera
> was mounted on a regular ballhead so there is some parallax error.
>
> Would a different optimization strategy solve the problem?
>
> Is there a workable post processing strategy to fix the errors?

I haven't really found a foolproof method, as it depends on the nature of
the errors.
I tend to optimise in steps, adding additional parameters at each step.
Also, for parallax errors, you can try to remove control points on very
close objects, and also add exclude masks to close objects in one of the
overlapping images. This can be a trial and error process.

>
> If I retook the pictures with a fixture that allows the camera to rotate
> around the zero parallax point, would the problems go away?

That should fix any alignment issues that are due to parallax.
It is possible to shoot hand held and avoid parallax by being careful to
rotate yourself and the camera about the zero parallax point.

Cheers,
--
Regards,
Terry Duell

[Sean Greenslade]

For the types of small misalignments that I see in this image, a nodal
rotator would be the best fix. I built one myself and spent a while
adjusting it to align properly with my camera.

I've also developed a bunch of strategies for how to deal with these
issues. The biggest one is try to get the main subject(s) entirely in
frame & in focus in at least one shot. It can be maddening to have a
seam going down a main focal point because it just happened to land
in between two shots.

Also (though it doesn't really help for your particular picture), if
there are areas of low contrast (white walls, unpatterned carpet, etc.),
you can force your seams to happen in those areas by using include and
exclude regions. I've found using exclude regions is gentler, since an
include region essentially translates to an exclude region on every
other image that touches that same region. By leaving some of the
low-contrast areas from both images in the seam area and making the
high-contrast areas appear in only one image, enblend is forced to put
the seams in the low-contrast areas where they are less noticable.

--Sean