PTGui "flips" pano upside down on second optimisation

[floz]

Hi there,

I'm having the following issue: PTGui, having detected a decent set of
control points ("Align Images") and optimised the alignment (which
ends with "Good" or even "Very Good"), shows the panorama correctly
oriented (i.e. floor is on the bottom of the image, ceiling on top).

However, if I then run a second optimisation run (initialise and
optimise) the pano is flipped upside down... (each image's Roll
parameter gets set to something around 180°; however, I don't want to
disable optimising roll, as my horizon is never perfect...).

What's up with that, and how can I prevent this from happening?!

Thanks for any input!!

[Erik Krause]

Am 05.12.2010 22:22, schrieb floz:
> However, if I then run a second optimisation run (initialise and
> optimise) the pano is flipped upside down...

Why do you initialize again? It should be sufficient to optimize only.

> (each image's Roll
> parameter gets set to something around 180�; however, I don't want to

> disable optimising roll, as my horizon is never perfect...).
>
> What's up with that, and how can I prevent this from happening?!

Disable Roll just for the first image. Only enable it if you have
horizontal or vertical control points (PTGui does this automatically
after a warning on the next optimizer run).

--
Erik Krause
http://www.erik-krause.de

[floz]

On Dec 5, 9:49 pm, Erik Krause <erik.kra...@gmx.de> wrote:
> Am 05.12.2010 22:22, schrieb floz:
>
> > However, if I then run a second optimisation run (initialise and
> > optimise) the pano is flipped upside down...
>
> Why do you initialize again? It should be sufficient to optimize only.
>
> > (each image's Roll

> > parameter gets set to something around 180 ; however, I don't want to

> > disable optimising roll, as my horizon is never perfect...).
>
> > What's up with that, and how can I prevent this from happening?!
>
> Disable Roll just for the first image. Only enable it if you have
> horizontal or vertical control points (PTGui does this automatically
> after a warning on the next optimizer run).

Well the issue happens even with vertical control lines place for
straightening...

>
> --
> Erik Krausehttp://www.erik-krause.de

[PTGui Support]

Hi Floz,

Could you send me your project file (just the .pts) at sup...@ptgui.com ?

The problem is very easy to fix: just press any of the two 'rotate'
buttons in the Project Assistant twice.

Joost

[Erik Krause]

Am 06.12.2010 10:50, schrieb floz:

> Well the issue happens even with vertical control lines place for
> straightening...

Strange. Would be interesting whether this happens only if you
initialize again or if it happens on a simple optimizer run as well. I
guess no...

[floz]

Dear Joost,

thanks for looking into this.

I've uploaded the project file here:

http://www.2shared.com/file/fu0XN2RP/p5_upstairs.html

Currently, the panorama is correctly oriented, but when I chose
"Initilize and optimize" it gets flipped upside down . . . Control
point alignment is "Good".

Thanks and best wishes,

Florian

On Dec 6, 11:01 am, PTGui Support <supp...@ptgui.com> wrote:
> Hi Floz,
>

> Could you send me your project file (just the .pts) at supp...@ptgui.com ?

[DennisS]

> Why do you initialize again? It should be sufficient to optimize only.

Sometimes when I bring in the Nadir patch shot and use viewpoint
correction (as the last step in the stitching process), the maximum
error distance goes into the 1000's. The entire panorama is totally
messed up even though the maximum error prior to bringing in the Nadir
patch was under 2. Since I know that all the settings (control
points, lens, shift etc...) are correct, I use "initialize and
optimize" to set everything right. Most times I get the entire
panorama flipped upside down. I have to flip all the images back.
The panorama then looks as it should.

[Ken Warner]

I've seen all that stuff in PTGui 8.3.10. When the pano
flips upside down, I just use the numeric transform thing.

[John Houghton]

On Dec 6, 11:50 pm, DennisS <den...@dlsphoto.net> wrote:

> Sometimes when I bring in the Nadir patch shot and use viewpoint
> correction (as the last step in the stitching process), the maximum
> error distance goes into the 1000's.  The entire panorama is totally
> messed up even though the maximum error prior to bringing in the Nadir
> patch was under 2.

To recover the situation existing before the optimization, just run
Edit->Undo (ctrl+z). To prevent the panorama being messed up when
optimizing the nadir, uncheck the y,p,r parameters of the other images
and also the lens parameters. Also, saving the project file is not a
bad idea before embarking on any tricky bits of optimization.

John

[DennisS]

> To recover the situation existing before the optimization, just run
> Edit->Undo (ctrl+z).  To prevent the panorama being messed up when
> optimizing the nadir, uncheck the y,p,r parameters of the other images
> and also the lens parameters.  Also, saving the project file is not a
> bad idea before embarking on any tricky bits of optimization.
>
> John

Or just go to the main tab and hit the counter clockwise circle twice
to rotate all the images 180 at the same time. Two mouse clicks puts
things right again. With all the other very powerful features of
PTGui, I am willing to put up with this very minor annoyance since
the fix is only two mouse clicks away. Well three, if you count the
click to get to the first tab. I just wish the numbers on the CP tab
screen were underlined when there is a control point pair. That is a
major annoyance.

[John Houghton]

On Dec 7, 12:32 pm, DennisS <den...@dlsphoto.net> wrote:
> Or just go to the main tab and hit the counter clockwise circle twice
> to rotate all the images 180 at the same time.  Two mouse clicks puts
> things right again.

That solution to the upside down panorama has already been suggested
by Joost, but it won't help when the "the maximum error distance goes

into the 1000's. The entire panorama is totally

messed up", which is the point I was replying to. The panorama would
be just as messed up after being rotated through 180 degrees.

John

[Erik Krause]

Am 07.12.2010 00:50, schrieb DennisS:
> Sometimes when I bring in the Nadir patch shot and use viewpoint
> correction (as the last step in the stitching process), the maximum
> error distance goes into the 1000's.

It's always a good idea to roughly align the additional image prior to
optimize viewpoint correction. This can be done manually in the pano
editor or just by placing two or three control points and optimize with
viewpoint correction off. Once the image is in place you can set more
control points and switch viewpoint correction on.

[DennisS]

I guess you guys do not quite get what I have said.

The panorama stitches great. I can have an maximum error that is very
small. If I was not patching the Nadir, I would be done and move on
to the next panorama. On occasion, when I bring in the patch, assign
control points between the patch and Nadir, turn on viewpoint
correction for the patch, in an attempt to get the maximum error down,
I try "initialize and optomize" just to see what would happen. The
all pictures are flipped upside down and the panorama is still
stitched, but upside down. The maximum error goes through the roof.
Three mouse clicks and things are put back right. While I agree that
fixing the issue that is causing the photos to flip is the best
solution (for the user), I think more time should be spent fixing
other issues and adding more features when the solution is at most 3
mouse clicks away. Not all panoramas do this, but when it happens, it
is very easy to fix.

[DennisS]

Even with version 9.1.9 the pano still flips upside down.

 

While stitching my latest series of panos I discovered one cause.  Although I cannot force a pano flip, I can prevent it from flipping again once it happens.

 

I first get the pano to stitch prior to adding the hand held Nadir patch shot.  When I add a Nadir patch shot, I mask out the area that I do not want to use.  I then manually assign control points to the Nadir and the first image from the series.

After I get several points assigned I turn on viewpoint correction then optimize.  If everything looks good I then go to the next image in the series,

draw a box around the masked area in the Nadir patch shot and select "assign control points here".  If all is right I get a bunch of new control points.

 

PTGui will assign control points inside the mask.  From what others have posted PTGui should not be doing this. 

PTGui has always assigned control points inside a masked area when I use "generate control points here".

 

These control points inside the mask area are what sometimes causes the pano to flip upside down when doing an optimize or initialize and optimize. 

Removing control points inside the mask fixes the issue and the pano no longer flips upside down.

 

 

[PTGui Support]

Hi Dennis,

On 26/04/14 16:14, DennisS wrote:
> optimize. If everything looks good I then go to the next image in the
> series,
> draw a box around the masked area in the Nadir patch shot and select
> "assign control points here". If all is right I get a bunch of new
> control points.
> PTGui will assign control points inside the mask. From what others have
> posted PTGui should not be doing this.

Well, 'Align Images' and 'generate control points' function in the
Control Points menu indeed will not add control points in any masked area.

But the 'generate control points here' will add control points even in
masked areas.

> PTGui has always assigned control points inside a masked area when I use
> "generate control points here".
> These control points inside the mask area are what sometimes causes the
> pano to flip upside down when doing an optimize or initialize and optimize.

If this happens again, please Undo the last optimization, save the
project and send it to me so the problem can be fixed.

Joost

[DennisS]

http://www.dlsphoto.net/FlippedPano.zip

 

Download the project file with full res .tif images.

 

Open the project.  Select "initialize and optimize".  The pano flips upside down.

 

Undo.

 

Delete control point #6 between images 3 and 4.  It is in the masked area.  Initialize and optimize no longer flips the pano upside down.

 

Please let me know when the file has been downloaded so I can pull it.

 

Remember that this project is a work in process.  There are still stitching and exposure issues to correct.